Merge pull request #31 from kinnalru/develop

Add support for GIT_DIR
if repo already has history - recript it

you must disable crypt filtering in .git/info/attributes
Ex: #* filter=encrypt diff=encrypt
then run gitcrypt recrypt from top of repository
crypthistory command refactored
enable/disbale and 'recrypt' commands
permission fix
some experiments on sshkey encryption
tmp
experiments still going
almost work
some features
some fixes
ready