Return the name part of the email address in the 'to' hash

I need this for a project I am working on and I think it doesn't go against what the purpose of this gem is. Wow, that was a really awkward way to say that. 

I am not thrilled with how I had to test this. I had to pass name: nil to a lot of them which I think is not what we want.  It looks like the test data is setup in each test so it may be best to change 

```
    @hash = {
      full: 'Bob <bob@example.com>',
      email: 'bob@example.com',
      token: 'bob',
      host: 'example.com',
      name: 'Bob',
    }
```
to
```
    @hash = {
      full: '<bob@example.com>',
      email: 'bob@example.com',
      token: 'bob',
      host: 'example.com',
      name: nil,
    }
```

You can see what I'm talking about here: https://github.com/r38y/griddler/commit/db8dbeeb080fed8a76a68f37a02ab64ce5026fca

Actually, I'm not sure one way is better than the other.