change namespaces in XML
var mNamespaces = {
"sap.ui.unified":"unified",
"sap.ui.core.mvc":"mvc",
"sap.ui.core":"core",
"sap.ui.layout.form":"f",
"sap.ui.layout":"l"
};
_.forEach(mNamespaces, function(short, namespace) {
var re = new RegExp(namespace, 'g');
sXML = sXML.replace(re, short);
});
//OR
for (var name in mNamespaces){
var re = new RegExp(name, 'g');
sXML = sXML.replace(re, mNamespaces[name]);
}