Change PhoneNumber to Phone

And all the changes that happen to go with that.

Removing "Number" from the model name makes for a better abstraction. Since a Phone has many attributes that happen to be numbers, it was a little confusing.
Add some landing pages and redirects for users
Make phone show view and add keypad
Improve phone show layout
Allow instance-save editing and tweak layout
Add todos
Improve browser phone loading UI
Provide a bare bones admin phone list