bug-63 lock card mode screen orientation
Merge pull request #16 from thomas771020/bug-63-lock-card-mode-screen-orientation

bug-63 lock card mode screen orientation, r=john-hu
bug-56: do the followings:
1. add download activity
2. add listadapter for language
3. change wordsstorage to support one db for a lang and category
combination.
4. add dialogutils
5. add errorutils
6. option dialog for partial downloaded db