Add a table for mapping cards to deck

Adds a m to n table for mapping
cards and decks
Refactor content handling

Makes DAO for the different entries in the content provider
database
Connecting cards and decks with a m to n table
Refactor m to n database use

Refactors and adds code to make
the deck-card entry used.

Still got a lot to change to
make it work, and there are some seroius refactoring
required.
Names should be changed.
There are a mix of these:
Card (flashcard, cardentry, flashcardtable ...)
Deck
DeckCardMap