Adding InvalidView and verify_invite views to whitelist (user should be able to access these without being in beta).

Enforcing login requirements before invitee with new code can be validated.  If user is not logged in, she is redirected to auth login page.  If auth 'next' feature is used, a successful login will then redirect to VerifiedView view.

.gitignor-ing Vagrant settings used for local development

Added test scenario for invalid Invite Code
Cleaned up one-liner docstring and reverted .gitignore to remove Vagrant references
Merge pull request #44 from mypetyak/master

Whitelisting a few non-beta views + enforcing login before Invite validation