synchronization with beta branch: introduced FBReaderApp.ExternalBook field
Merge branch 'master' into ice-cream-sandwich
Merge branch 'ice-cream-sandwich' into yota2
Merge branch 'yota2' into kindle
introduces FBReaderApp.getCurrentBook()
Merge branch 'master' into ice-cream-sandwich
Merge branch 'ice-cream-sandwich' into yota2
Merge branch 'yota2' into kindle