Merge pull request #531 from danielhass/toast_replacement

Futher Toast replacements
Added possibility to enter custom key length. Added key length limitations, according to issue #102 and SpongyCastle specification.
Fixed coding style.
Merge pull request #536 from gogowitczak/custom-key-length

Added possibility to enter custom key length.
Update copyright timespan for Thialfihar
Change license from ASLv2 to GPLv3 where possible
Merge pull request #537 from thi/change-license-to-gpl

Change license to gpl
Introduce ProviderHelper.NotFoundException, remove dead code
Fix decryption of messages/files encrypted for multiple public keys
Use NotFoundException in more places
Modified Spinner values for CreateKeyDialog. Added info for user about custom key length restrictions.
Fix DECRYPT and SEND intent
KeychainIntentService instead of APG
Merge pull request #539 from gogowitczak/custom-key-length-info

Modified Spinner values for CreateKeyDialog. Added info for user about custom key length restrictions.
Hide keyboard after hiding custom key length field
Cleanup in SelectKeyCursorAdapter
Replaced Toasts in ImportKeysOrCodeFragment
Removed unused Toast import in ViewKeyActivityJB
Replaced Toasts in ViewKeyActivity