Even if we move away from php-gettext in the future, it's easy to
write a quick T_() as a simple wrapper; it's not so easy to rewrite
PHP to allow redeclaration of a function.
Prototype functionality where possible (particularly for Ajax). Move our JS
into lib/javascript (I dropped kajax as an external module since the new
ajax.js is completely different apart from function headers.) Remove unused
JS functions from base.js.