Merge pull request #7997 from openfun/rmoch/i18n_problem_explanation_title

i18n lon-capa problem explanation title

AUTHORS

@@ -211,3 +211,4 @@ Amir Qayyum Khan <amir.qayyum@arbisoft.com>
 Jolyon Bloomfield <jolyon@mit.edu>
 Kyle McCormick <kylemccor@gmail.com>
 Jim Cai <jimcai@stanford.edu>
+Richard Moch <richard.moch@gmail.com>

common/lib/xmodule/xmodule/js/src/problem/edit.coffee

@@ -201,6 +201,8 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
 #
   @markdownToXml: (markdown)->
     toXml = `function (markdown) {
+      // Translators: This is the title of the text explaining a problem
+      var explanation_title = gettext("Explanation");
       var xml = markdown,
           i, splits, scriptFlag;
 
@@ -348,14 +350,15 @@ class @MarkdownEditingDescriptor extends XModule.Descriptor
       });
 
       // replace explanations
+
       xml = xml.replace(/\[explanation\]\n?([^\]]*)\[\/?explanation\]/gmi, function(match, p1) {
-          var selectString = '<solution>\n<div class="detailed-solution">\nExplanation\n\n' + p1 + '\n</div>\n</solution>';
+          var selectString = '<solution>\n<div class="detailed-solution">\n' + explanation_title + '\n\n' + p1 + '\n</div>\n</solution>';
 
           return selectString;
       });
-      
+
       // replace labels
-      // looks for >>arbitrary text<< and inserts it into the label attribute of the input type directly below the text. 
+      // looks for >>arbitrary text<< and inserts it into the label attribute of the input type directly below the text.
       var split = xml.split('\n');
       var new_xml = [];
       var line, i, curlabel, prevlabel = '';