[#2319] Clean up field names before rendering the table

See datopian/datahub#465 for details

Patching local recline but a PR has been sent to the recline repo:

datopian/datahub#466

ckanext/reclinepreview/theme/public/vendor/recline/recline.js

@@ -4494,10 +4494,16 @@ my.SlickGrid = Backbone.View.extend({
         return value;
       }
     };
+
+    function sanitizeFieldName(name) {
+      var sanitized = $(name).text();
+      return (name !== sanitized && sanitized !== '') ? sanitized : name;
+    }
+
     _.each(this.model.fields.toJSON(),function(field){
       var column = {
         id: field.id,
-        name: field.label,
+        name: sanitizeFieldName(field.label),
         field: field.id,
         sortable: true,
         minWidth: 80,