Added support for entity codes so that it for instance is possible to represent a " with #quot; and a heart with #9829; This differs from the regular html codes in that the leading & isreplaced with a dsh and for dec codes dropped. This as referenced in issue #219.

src/mermaid.js

@@ -20,6 +20,7 @@
 var mermaidAPI = require('./mermaidAPI');
 var nextId = 0;
 var log = require('./logger').create();
+var utils = require('./utils');
 
 module.exports.mermaidAPI = mermaidAPI;
 /**
@@ -122,12 +123,33 @@ var init = function () {
         txt = txt.replace(/>/g,'>');
         txt = txt.replace(/</g,'&lt;');
         txt = he.decode(txt).trim();
-
+        txt = exports.encodeEntities(txt);
+        if( utils.detectType(txt) === 'sequenceDiagram'){
+            txt = he.decode(txt).trim();
+        }
         mermaidAPI.render(id,txt,insertSvg, element);
     }
 
 };
 
+exports.encodeEntities = function(text){
+    var txt = text;
+
+    txt = txt.replace(/#\w*;?/g,function(s,t,u){
+        var innerTxt = s.substring(1,s.length-1);
+
+        var isInt = /^\+?\d+$/.test(innerTxt);
+        if(isInt){
+            return '&#'+innerTxt+';';
+        }else{
+            return '&'+innerTxt+';';
+        }
+
+    });
+
+    return txt;
+};
+
 exports.init = init;
 exports.parse = mermaidAPI.parse;
 /**