OO-2110 fix wrong o_clearfix and fix clearing for info page start button

src/main/java/org/olat/modules/video/ui/_content/video_preview.html

-<div class="o_video_run o_block_large_bottom o_clearfix">
+<div class="o_video_run o_block_large_bottom clearfix">
 	<div class="olatFlashMovieViewer">
 		<video id="$r.getId("o_vid")" width="$width" height="$height" controls  autoplay preload="none" oncontextmenu="return false;" class="o_video">			
 	    	<source type="video/mp4" src="$mediaUrl/$filename" />

src/main/java/org/olat/modules/video/ui/_content/video_run.html

-<div class="o_video_run o_block_large_bottom o_clearfix">
+<div class="o_video_run o_block_large_bottom clearfix">
 	<div class="olatFlashMovieViewer">
 		<video id="$r.getId("o_vid")" width="$width" height="$height" poster="$masterUrl/poster.jpg" controls  preload="none" oncontextmenu="return false;" #if( $autoplay ) autoplay #end class="o_video">			
 	    	#foreach($video in $videos)

src/main/java/org/olat/repository/ui/list/_content/details.html

@@ -25,7 +25,7 @@
 		#end
 		
 		#if($r.available("start"))
-		<div class="o_start_wrapper o_clearfix">
+		<div class="o_start_wrapper">
 			<div class="o_start_inner">
 				$r.render("start")
 			</div>

src/main/java/org/olat/user/_content/homepagedisplay.html

@@ -5,7 +5,7 @@
 	#end
 
 	<div class="o_visitingcard_content">
-		<div class="o_visitingcard_image o_block o_clearfix">	
+		<div class="o_visitingcard_image o_block clearfix">	
 			<div class="pull-left">$r.render("image")</div>
 			#if($r.available("logo") && $r.visible("logo"))
 				<div class="pull-right">

src/main/webapp/static/themes/light/modules/_repository.scss

@@ -38,6 +38,7 @@
 	}
 
 	.o_start_wrapper {
+		clear: both;
 		margin: 2em 0 -10px 0;
 		text-align: right;
 		.o_start_inner {