OO-2729: remove version von MathJax in code, change cdn to our own

src/main/java/org/olat/core/commons/fullWebApp/_content/fullwebapplayout.html

@@ -51,7 +51,7 @@ function o_start() {
 	o_info.initialPageLoadFinished = true;
 }
 function o_mathjax(fct_success) {
-	jQuery.ajax("${r.mathJaxCdn()}2.6-latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML", {
+	jQuery.ajax("${r.mathJaxCdn()}MathJax.js?config=TeX-AMS-MML_HTMLorMML", {
 		cache: true,
 		dataType: "script",
 		success: function() {

src/main/java/org/olat/core/gui/control/generic/iframe/IFrameDeliveryMapper.java

@@ -600,7 +600,7 @@ public class IFrameDeliveryMapper implements Mapper {
 		public void appendJsMath() {
 			append("<script type=\"text/javascript\" src=\"");
 			append(WebappHelper.getMathJaxCdn());
-			append("2.6-latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML\"></script>\n");
+			append("MathJax.js?config=TeX-AMS-MML_HTMLorMML\"></script>\n");
 			append("<script type=\"text/javascript\">\n");
 			append("MathJax.Hub.Config({\n");	
 			append(" extensions: [\"jsMath2jax.js\"],\n");

src/main/resources/serviceconfig/olat.properties

@@ -536,7 +536,7 @@ allow.cross.origin.domain.values=*,www.frentix.com
 # MathJAX CDN
 ########################################################################
 
-mathjax.cdn=//cdn.mathjax.org/mathjax/
+mathjax.cdn=//mathjax.openolat.org/mathjax/2.7-latest/
 
 ########################################################################
 # Database settings