now creates wallet specific directory and backup directories within
private key backups uses new backup directory structure
rolling backup using new directory structure
now backups unencrypted wallets too
 added AES total file encryption methods
unencrypted backups now file encrypted when wallet password is added
now creates backups on wallet creation
more unit tests
improved wallet recovery to use wallet_backup and wallet_unenc_backup
fixed NPE when wallet and backups fail
improvements to calculating best backup candidates
 sets version in info file after load from wallet type
(in case backup loaded is different type)
updated tests
 bumped version of bitcoinj being used
refactored and added BackupManager
minor code refinements
can now open wallet.cipher files
open wallet now moves key, wallet and info files into subdirs
initial moving of key, wallet and info files now working
tidied up code slightly. Also removed some transient fields fromt the info files before persisting