Checkpoints instead of genesis sync

Switching over to checkpoints
Need to find out how bitcoin-wallet syncs wallets with incomplete
blockchains...
Currently, checkpoints init the blockchain fine, and syncing works
Had to add some logic to litecoinj to make it validate properly
when verifying difficulty changes when syncing.
It seems like this makes the chain sync right

The chain now syncs with the oldest key creation date in the wallet.  This
means if you use new keys, it only pulls in the checkpoint and sync takes
around 10-15 minutes.  I have rather old keys, so I have to sync a few
weeks/months.  Better than from genesis always though!!
Going to 1.07

Things are getting fixed.  Camera works now on certain devices where it didn't before.  Did a work around for the thread crash
Adding libscrypt
Getting ready to merge checkpoints
Merge branch 'checkpoints'

Conflicts:
	.idea/compiler.xml
	.idea/workspace.xml
	wallet/wallet.iml