add user data and message to lock command

This is a small change, but interesting for known the reason of the lock, and can contact the person who made the lock.

```
[rodmen@localhost Magallanes]$ bin/mage lock to:env
Starting Magallanes

Your name (enter to leave blank): Rodrigo Mendez
Your email (enter to leave blank): rodmen@gmail.com
Reason of lock (enter to leave blank): I made some changes, please keep it       
        Locked deployment to env environment

Finished Magallanes
```
```
[rodmen@localhost Magallanes]$ bin/mage deploy to:env
Starting Magallanes

        This environment is locked!

Locked environment at date: 2014-06-26 14:19:37
Locked by Rodrigo Mendez (rodmen@gmail.com)
I made some changes, please keep it
Finished Magallanes

```