Format @Date to ISO 8601 format. Fixes #12725, Closes gh-957

grunt.js

@@ -365,10 +365,19 @@ module.exports = function( grunt ) {
 				}
 			});
 
-			// Embed Date
 			// Embed Version
-			compiled = compiled.replace( "@DATE", new Date() )
-				.replace( /@VERSION/g, version );
+			// Embed Date
+			compiled = compiled.replace( /@VERSION/g, version )
+				.replace( "@DATE", function () {
+					var date = new Date();
+
+					// YYYY-MM-DD
+					return [
+						date.getFullYear(),
+						date.getMonth() + 1,
+						date.getDate()
+					].join( "-" );
+				});
 
 			// Write concatenated source to file
 			file.write( name, compiled );