I'm using ssh key for git, after I added ssh key and check it authenticated successfully. But I still cannot commit code

```
$ eval "$(ssh-agent -s)"
Agent pid 2599

$ ssh-add ~/id_rsa
Identity added: /home/vagrant/id_rsa (/home/vagrant/id_rsa)

$ssh -T git@github.com
Hi my-git-username! You've successfully authenticated, but GitHub does not provide shell access. 

```

But I cannot do commit

```
$ git commit -m "Develop Dockerfile for shopContainer"

*** Please tell me who you are.

Run

   git config --global user.email "you@example.com"
   git config --global user.name "Your Name"

to set your account's default identity.
Omit --global to set the identity only in this repository.

fatal: unable to auto-detect email address (got 'vagrant@vagrant-ubuntu-trusty-64.(none)')

```