`XF.log` added for debug purposes

Removing `console.log` from the framework. Replacing it with `XF.log`.
XF logging can be turned off using `debug` property in application
settings (true/false).
Removing `hideAddressBar` utility.

Not needed anymore. Bye, good ol’ times!
Extending new App with all methods passed

All methods passed into constructor `new XF.App` except settings will
be added to the instance.
Fix: checking if ajaxSettings exist
Templates caching fixed

There is no more clearing of all localStorage