Installer fixes & theme changes

I made a huge mess with my last pull request, so this is the somewhat cleaner version

1) Old "ghost" theme renamed to oh-ghost
2) New ghost theme featuring the following changes:
- Removed OHSystem and Ghost logo to make it less personalized (credits in the footer are still kept, of course)
- Search button removed (not needed because of the auto complete)
- Search bar placed next to the menu to save space and achieve a cleaner layout

3) Some inline CSS moved to style.css (#search_results_live)
4) Fixed "Facebook Login" appearing when it's disabled
5) Fixed SQL imports for heroes and items, they didn't work properly
6) Added GeoLiteCity database to avoid errors
7) Added a missing /img/pp folder