Adding browserify support

Run drive with --browserify to switch browserify support on and test against it

* added browserify-specific client-side suite for triggering test runs
* added options --noparse and --transforms passed directly to browserify on bundle
* served tests get unamdified (require dependency removed, requires rewritten to browserify'd namespace)
* added find_requirements module for walking tests AST for dependencies and namespacing them for browserify

There are some uglyish overrides in place currently for testing (note file validation always returns true, etc)