Instead of a single line with 500000 characters use nicely formatted JSON.
Sort the lists in engine_languages.py so when updating it is possible to
more easily see the differences (search engines do change the order their
languages are listed in)
Add match_language function in utils to match any user given
language code with a list of engine's supported languages.
Also add language_aliases dict on each engine to translate
standard language codes into the custom codes used by the engine.