Remove forge from Widget

This leaves Widget vulnerable to being constructed like a ViewModel. Oh well.
Make handle_get and turn post into handle_post to match
Set values *after* constructing!
reword crappy bit in readme
Lazyify the data applied to Widgets
Bootstrap would help.
Docblocks
Default handle_* return false not true
Provide and use _errors array for convenience
Conveniently set errors on the view
Protect against HMVC requests by redirecting to the main URI