Mod to have language keys automatically recognized by the template parser

[eluser]Yoglets[/eluser]
Well, good news and bad news. It's faster and slower. If you have a large number of unused keys and a very small template, it's faster. But as soon as the template grows, even if the number of unused keys remains large, the cost of the one preg_match_all() call offsets all of the failed str_replace() calls. I'll try various combinations to see if maybe there's a somewhat predictable pattern, like only do the replacement if the template is less then 1K in size or something.