Handle a few more edge cases:
- improve the unbottled output heading so it makes sense when we're
outputting bottles that are ready to bottle
- output already bottled formulae if named
- handle Linux/Mac requiring formulae and output if named
- output bottle unneeded/disabled formulae if named
- use green/yellow/red for bottles ready to be built now/later/never
- When testing `brew unbottled <formula>` this crashed because I, as a
maintainer, have `HOMEBREW_NO_ANALYTICS` set on all my machines to
avoid polluting the analytics with test installs.
```
❯ brew unbottled
==> Getting formulae...
==> Getting analytics data...
Error: undefined method `[]' for nil:NilClass
/usr/local/Homebrew/Library/Homebrew/dev-cmd/unbottled.rb:89:in `formulae_all_sort_installs_from_args'
/usr/local/Homebrew/Library/Homebrew/dev-cmd/unbottled.rb:49:in `unbottled'
/usr/local/Homebrew/Library/Homebrew/brew.rb:119:in `<main>'
```
