Improves check for xAPI version.
Adds .
Corrects check.
Uses `any` to selectMethod.
Begins to tidy up ActivityController.

Preferring `\LockerRequest::hasParam(x)` over `isset($this->params[x])`.
Completes tidy up of ActivityController.
Tidies up document controllers.
Improves tests.
Tidies up StatementController.
Cleans up BasicRequestController.
Corrects DocumentControllers.
Fixes tests.
Merge pull request #425 from LearningLocker/issue/412

Issue/412