feature: increase API compatibility with FakerElixir

I just migrated from the unsupported FakerElixir library to Faker and was disappointed that several of my more widely used interfaces don't exist here. It would be helpful for others trying to migrate here (as recommended in glowing terms by FakerElixir) if more of the FakerElixir API was covered.

The two missing APIs used most frequently in my code are FakerElixir.Internet.email/1 which accepts a name and turns that into a valid email address with a random domain, and FakerElixir.Internet.username/1 which effectively does the same thing from a name to a username.

I have also noticed File.name/1, and some variations in the functions provided by Phone such as not having cell and home.

I don't expect perfect compatibility but a few additional APIs would certainly have helped me.