Fix theme

Theme copyright.

Added theme copyright for Twenty Fifteen & Twenty Sixteen.

Prepare quick release

Prepare quick release since even though only small changes but its
important. See commit #2fca100

Improving template engine

Improving template engine for more flexible theming. Add
cache.expiration.

Improvements

Update

Improve custom menu

Add active menu link to custom menu

Prepare release

Fixes

PHP 5.3 compatibility