Dashboard look & feel almost complete
Too early to work on progress.xml
Removed useless import
Added LevelProgression support
Connected LevelProgression to core
Added hints on wrong API key
Fixed hide/show of lessons_now
Made lessons hyperlink to be "unlock" only
Fixed bug causing lessons to be always 0
Fixed bug preventing lessons link to work
Implemented userinfo caching; saves one call at startup
Removed a couple of useless imports
Split DashboardData into mandatory and optional stuff
Reversed gradient (looks better this way)
Made prog bar max=100 explicitly
Added progress bar handling
Removed source of NullPointerException's
Fixed NullPointerException on deserialize
If API key is wrong, switch back to error screen
Removed WK URL from prefs. Consistent with the "review now" link