possibility to transcrypt already encrypted variables with new public key

[Snooz82]

If a key has been compromised it could be nessesary to use different key pairs.

CryptoLibrary shall have a possibility to decrypt all data with "old" private key and encrypt again with new public key. This shall be done on a full foldertree.

CryptoLibrary will search for all Strings matching r'crypt:.*[^\s]' and try to transcrypt.