Merge pull request #151 from maniac103/for-upstream

My improvements & fixes
Fix unbalanced super class call.
Properly use constants.
Replace restartLoader() by Loader.onContentChanged().

Just restarting the loader won't force a data refresh.
Switch to SherlockProgressFragment.

Fixes calling invalidateOptionsMenu() on API 10.
Suppress errors for using
SherlockFragmentActivity.invalidateOptionsMenu().
Store theme setting in a format controlled by us.

R.style.* can change over time (dependant on build settings, used
libraries etc.), so we should rather not use it as a theme setting
lookup key and blindly trust it on reading from persistent storage.
Fix unused imports.