Implement `dolt init --fun`

[timsehn]

The dolt logo is inspired by a commit hash d01t.

It would be cool if we had an option to have a dolt initial commit be rerolled until the first four characters matched the following pattern:

1. d, o l, t in order
2. any uppercase or lowercase d, o, l, t
3. 0 or 1 can replace l or t

I think this should be a hidden option not in the docs.