Setup initial docs structure

* Complete overview
Add Authorization topics

* Ported over both Authorization topcs
Removing generated snippets directory
Ignoring generted snippets directory for docs
Adding a "Testing" mode to FubuMode
added the new FubuMode.Testing mode for automated testing scenarios
FlashProvider now uses ISessionState. Moved the default back to FlashProvider
Got UTs around the SimpleSessionState
Fixes a stack overflow in the StandInCurrentHttpRequest.
Merge pull request #532 from joemcbride/full-url-bug

Fixes a stack overflow in the StandInCurrentHttpRequest.