Allow font to be set in TextAppearance for custom font widgets
Show current feed name in bold text

Harder than it seems, had to change callback listener to base class
FragmentAcitivtyWithMenu and also have App be the one to hold the
"current feed" property.
Get media type from MediaContent class
Fixed flashing images

Bug #3165
Merge pull request #43 from N-Pex/courier

Make current feed bold text in menu and fix flickering images.