OO-4072 Adjust colors in OO theme, reduce filesize login bg

src/main/webapp/static/themes/openolat/_openolat_config.scss

 /* OpenOLAT colors */
-$o-brand-turquoise				: rgb(0,163,173);
-$o-brand-red					: rgb(166,9,61);
-$o-brand-green					: rgb(0,106,82);
-$o-brand-orange					: rgb(255,184,28);
-$o-brand-grey					: rgb(90,90,90);
-$o-brand-black					: rgb(71,55,41);
+$o-brand-chocolate				: rgb(52,44,36);
+/* $o-brand-chocolate				: rgb(71,55,41);  more brownish */
+$o-brand-sprout					: rgb(178,207,66);
+$o-brand-forest					: rgb(17,98,79);
+$o-brand-sea					: rgb(32,157,158);
+$o-brand-peach					: rgb(242,175,64);
+$o-brand-berry					: rgb(143,31,64);
+
+$o-brand-red					: rgb(214,0,28);
+$o-brand-green					: rgb(120,190,32);
+$o-brand-yellow					: rgb(254,219,0);
+$o-brand-grey					: rgb(166,166,166);
+$o-brand-black					: rgb(45,41,38);
+
 
 /* General colors */
-$brand-primary 					: $o-brand-turquoise; 		
+$brand-primary 					: $o-brand-sea; 		
 $brand-success					: $o-brand-green;		
 $brand-info  					: $o-brand-grey;
-$brand-warning					: $o-brand-orange;	
+$brand-warning					: $o-brand-peach;	
 $brand-danger					: $o-brand-red;
 
 $text-color						: $o-brand-black;
-$link-color						: $o-brand-turquoise;
-$link-hover-color				: darken($o-brand-turquoise, 10%);
+$link-color						: $o-brand-sea;
+$link-hover-color				: darken($o-brand-sea, 10%);
 $o-content-link-color			: $link-color;
 $o-content-link-hover-color		: $link-hover-color;
 $o-content-link-decoration		: underline;
 
-$headings-color					: $o-brand-black;
+$headings-color					: $o-brand-chocolate;
 $o-content-header-base-color	: $headings-color;
 $o-content-fieldset-legend-color: $headings-color;
 $o-dialog-header-color			: $headings-color;
@@ -28,8 +36,8 @@ $jumbotron-heading-color		: $headings-color;
 $o-login-header-color			: $headings-color;
 $o-coursesite-meta-title-color	: $headings-color;
 
-$o-bookmark-color				: $o-brand-red;
-$o-button-dirty-bg				: $o-brand-orange;
+$o-bookmark-color				: $o-brand-berry;
+$o-button-dirty-bg				: $o-brand-peach;
 $o-portfolio-editor-border-color	: $brand-primary;
 
 /* Login screen */
@@ -41,21 +49,21 @@ $o-login-form-bg-gradient-steps	: rgba(255,255,255,0) 0.2%, rgba(255,255,255,0.3
 infinite.jpg
 Pixaby License by https://pixabay.com/photos/away-avenue-trees-nature-infinite-2414983/
 
-christian-bg.jpg
-florian-bg.jpg
-holger-bg.jpg
-oo-bg.jpg
+christian.jpg
+marco.jpg
+holger.jpg
+openolat_award.jpg
 CC by frentix GmbH http://www.frentix.com 
 */
 
 
 $o-login-btn-register-color		: #fff;
-$o-login-btn-register-bg		: $o-brand-orange;
-$o-login-btn-register-border	: $o-brand-orange;
+$o-login-btn-register-bg		: $o-brand-peach;
+$o-login-btn-register-border	: $o-brand-peach;
 
 /* Course site start button */
-$o-coursesite-start-bg			: $o-brand-turquoise; 
-$o-coursesite-book-bg			: $o-brand-turquoise;
+$o-coursesite-start-bg			: $o-brand-sea; 
+$o-coursesite-book-bg			: $o-brand-sea;
 $o-coursesite-details-bg		: $o-brand-grey;
 
 /* Font family */

src/main/webapp/static/themes/openolat/email.css

-.o_email_body{font-family:"HelveticaNeue-Light","Helvetica Neue Light","Helvetica Neue",Helvetica,Arial,"Lucida Grande",sans-serif;max-width:768px}.o_email_body .o_email_content{margin:14px 0 14px 0;padding-left:12px}.o_email_body .o_email_content h1{background-color:#00a3ad;color:#fff;padding:20px 0 20px 12px;margin-bottom:30px;margin-left:-12px;font-size:x-large}.o_email_body .o_email_content strong{color:#00a3ad}.o_email_body .o_email_footer{font-size:smaller;color:#aaa;border-top:5px solid #00a3ad;padding:4px 12px;margin-top:1em}.o_email_body .o_email_footer a{color:#aaa}.o_mail_message .o_email_body{font-family:inherit}.o_email_body .o_email_button{color:#fff;background-color:#00a3ad;border-color:#008b94;border-radius:4px;padding:6px 12px;text-align:center;white-space:nowrap;vertical-align:middle;touch-action:manipulation;cursor:pointer;text-decoration:none}.o_email_body .o_email_button_group{margin-top:1em;margin-bottom:1em;text-align:center}.o_email_body .o_email_button_group a{margin-right:5px;margin-bottom:0.5em;font-weight:bold}.o_email_body .o_email_button_group a:last-child{margin-right:0}.o_email_body .o_email_button_group_left{text-align:left}.o_email_body .o_email_button_group_right{text-align:right}
+.o_email_body{font-family:"HelveticaNeue-Light","Helvetica Neue Light","Helvetica Neue",Helvetica,Arial,"Lucida Grande",sans-serif;max-width:768px}.o_email_body .o_email_content{margin:14px 0 14px 0;padding-left:12px}.o_email_body .o_email_content h1{background-color:#209d9e;color:#fff;padding:20px 0 20px 12px;margin-bottom:30px;margin-left:-12px;font-size:x-large}.o_email_body .o_email_content strong{color:#209d9e}.o_email_body .o_email_footer{font-size:smaller;color:#aaa;border-top:5px solid #209d9e;padding:4px 12px;margin-top:1em}.o_email_body .o_email_footer a{color:#aaa}.o_mail_message .o_email_body{font-family:inherit}.o_email_body .o_email_button{color:#fff;background-color:#209d9e;border-color:#1c8889;border-radius:4px;padding:6px 12px;text-align:center;white-space:nowrap;vertical-align:middle;touch-action:manipulation;cursor:pointer;text-decoration:none}.o_email_body .o_email_button_group{margin-top:1em;margin-bottom:1em;text-align:center}.o_email_body .o_email_button_group a{margin-right:5px;margin-bottom:0.5em;font-weight:bold}.o_email_body .o_email_button_group a:last-child{margin-right:0}.o_email_body .o_email_button_group_left{text-align:left}.o_email_body .o_email_button_group_right{text-align:right}
 /*# sourceMappingURL=email.css.map */

src/main/webapp/static/themes/openolat/images/OpenOlat_Logo_RGB.svg

@@ -4,8 +4,8 @@
 	 y="0px" viewBox="0 0 841.89 595.28" style="enable-background:new 0 0 841.89 595.28;" xml:space="preserve">
 <style type="text/css">
 	.st0{fill:none;}
-	.st1{fill:#00A3AD;}
-	.st2{fill:#473729;}
+	.st1{fill:#209d9e;}
+	.st2{fill:#342c24;}
 </style>
 <rect x="124.96" y="182.18" class="st0" width="67.52" height="67.52"/>
 <path class="st1" d="M281.59,291.76c0.23,6.38-2.26,12.46-7.11,17.3c-9.31,9.31-24.48,9.22-33.89-0.2l-16.98-17.11v0l16.98-17.11

src/main/webapp/static/themes/openolat/images/OpenOlat_Logo_claim_RGB.svg

@@ -4,8 +4,8 @@
 	 y="0px" viewBox="0 0 841.89 595.28" style="enable-background:new 0 0 841.89 595.28;" xml:space="preserve">
 <style type="text/css">
 	.st0{fill:none;}
-	.st1{fill:#00A3AD;}
-	.st2{fill:#473729;}
+	.st1{fill:#209d9e;}
+	.st2{fill:#342c24;}
 </style>
 <rect x="124.96" y="182.18" class="st0" width="67.52" height="67.52"/>
 <path class="st1" d="M281.59,291.76c0.23,6.38-2.26,12.46-7.11,17.3c-9.31,9.31-24.48,9.22-33.89-0.2l-16.98-17.11v0l16.98-17.11