Fixing some warnings that I discovered through unit testing under E_ALL

Fixing some warnings that I discovered through unit testing under E_ALL

* Functions.php:
(BSFunctions::FetchMicrotimeDiff): Refactored the local vars
* Template.php:
(BSTemplate::fetch): Fixed a warning generated by the uncached template counter
(BSTemplate::flush): Fixed a warning about the microtime diff because we weren't passing a microtime, just the seconds