AbstractLibrary has gone
Merge branch 'master' into library-service

Conflicts:
	src/org/geometerplus/android/fbreader/libraryService/LibraryShadow.java
	src/org/geometerplus/fbreader/library/AbstractLibrary.java
book serialization (in progress)
better book serialization
misc optimizations, first "working" version of book serialization/deserialization (missing things are marked with TODO comments)
book serialization is now usable
library service in operation ;)
a separate class BookCollection
BookCollection.build()
Library.startBuild() replaced with BookCollection.startBuild()
book removing code transferred to BookCollection class
BookCollection.getRecentBook(index)
move code moved from Library to BookCollection
no database field in Library class
Book.getById() => BookCollection.getBookById()
service connection in bookmarks activity (not used yet)
first service usage: open book from BookmarksActivity
BookCollectionShadow: a wrapper for LibraryInterface
more "architecture" around book serialization
bookmark serialization; used in BookmarksActivity