support for GIT_DIR environment var
Merge pull request #31 from kinnalru/develop

Add support for GIT_DIR
working with history available

 * enable/disbale commands
 * crypthistory/decrypthistory commands
 * recrypt command

if repo already has history - you can recrypt it
run gitcrypt recrypt from top of repository
Now you can you ssh-private key as password

Now you can use ssh-private key(also with passphrase) instead password

$ Generate a random password? [Y/n]n
$ Enter your passphrase: ~/.ssh/id_rsa
Merge branch 'sshencryption'
Release version 0.3.2