Updated tests, check that errors are cast into thx.error.Error

Also minor formatting changes
Replace Assert.isTrue(false) with Assert.fail(msg)
Added documentation. Allow instance creation on unsupported platforms.

They will throw an error if flush() is called, but the rest will work...
Add default for modRewrite (false by default)
Refactor: HttpApplication can handle multiple requests.

So the various events dispatch a context, not the application.

Updated the various modules to work.  HttpApplication tests passing.

UfrontApplication tests all failing at the moment.  I'll get on that soon...
Moved UrlFilters to be set at HttpApplication level, and
passed to HttpContext for each request
Fixes for UfrontApplication.  Most tests written, all now passing
Small fix to browser tracing
Only dispose session if it actually exists in the first place
Unit tests and fixes to ufront.web.Dispatch.  Consider it ready to use...

Small changes (eg, take method, not the whole context).  Should be stable API now
Add a few new results, add test placeholders
Include basic Controller.  Doesn't do much yet