issue2551270 - Better templating support for JavaScript Add (templating) utils.readfile(file, optional=False) and utils.expandfile(file, token_dict=None, optional=False). Allows reading an external file (e.g. JavaScript) and inserting it using tal:contents or equivalent jinja function. expandfile allows setting a dictionary and tokens in the file of the form "%(token_name)s" will be replaced in the file with the values from the dict. See method doc blocks or reference.txt for more info. Also reordered table in references.txt to be case sensitive alphabetic. Added a paragraph on using python's help() to get method/function/... documention blocks. in templating.py _find method. Added explicit return None calls to all code paths. Also added internationalization method to the TemplatingUtils class. Fixed use of 'property' hiding python builtin of same name. Added tests for new TemplatingUtils framework to use for testing existing utils.