Git.Internal: Add git
Git.Interanl: Add repository
Git.Internal: Make git MonadCatchIO instance
Oid: Define GitObject
Oid: Define Oid
Add Blob.hs
Blob: Add blob
Add Tree.hs
Tree: Define TreeBuilder
Tree: Add create
Tree: Define Treeable type class
Tree: Add write
Tree: Make Tree instance of GitTreeable
Tree: Make Blob instance of GitTreeable
Tree: Add Tree
Add Signature.hs
Signature: Define Signature
Signature: Define Email
Signature: Define Name
Signature: Add sign