Merge pull request #2 from natebrunette/master

Adding $firewall as a login parameter.
User Object based Auth

Updating User Login method to accept User objects instead of just roles to allow
for testing that requires a user object in the security context
Updating docs to match changes in functionality
Fixing missing parent constructor call
Fixed parent constructor call for tests with dataproviders [BC Break]

Fixing the parent constructor extensions to be last arguments in signature,
this will be a breaking change, but is required as a bugfix to move forward with 2.0.
Added assert for form submissions

Works similarly to HaphazardTestCase::assertGet().  Requires an additional
string that defines what to search for to find the submit button.  It will
override the csrf provider to always return true when it checks if the token is
valid.