Optimized images

All images optimalized via PNGGauntlet. The image quality unchanged, but
the files became smaller.
Adds Theme customization feature
Adds reset button to settings pages
authorUrl -> homepage
Hungarian translations updated

The Hungarian module translations updated for the latest OctoberCMS
build.
Throw AppExceptions so they are not logged
ThemeData now applies default values, Theme object will proxy to ThemeData
Merge pull request #800 from gergo85/master

Optimized images and update jQuery