Allow people to give model name or not, ask for it when needed

So the terminal UI should be:

- [x] People can give commands with or without user name prepended, so need to identify all types of commands whether they start at `magic[0]` or `magic[1]`

- [x] When people don't give a model when we need it for the code, ask for it and take it with `gets.chomp`

- [x] If people do give model name out of habit but we don't need it, ignore it.