This was moved to Keg, but looks like I forgot to get rid of it here.

This reverts commit da1caba17c624f03fa8e6fbe59683f57fb7ac17a.

Dependent can be bypassed with `--ignore-dependencies`.
This is now the default for `HOMEBREW_DEVELOPER`s.

This means that run_as_not_developer can be used in integration tests

With the way uninstall is set up at the moment, it's pretty difficult to
add functionality to both the --force and normal variants.

Extracting the racks and kegs to be uninstalled before uninstalling them
should make this easier.

@vladshablinsky pointed out that other Homebrew classes, like Dependency,
use #to_formula.

@ilovezfs pointed out that Homebrew generally uses "dependent", rather than
"dependant".

Suggested by @MikeMcQuaid

Closes #934.

hbc/qualified_token: simplify token parsing

FIX: cask changes /usr/local ownership recursively

add cask reinstall command

New name is HOMEBREW_CASK_TAP_CASK_REGEX

- Stop supporting archaic "user-repo/token" syntax
- Move regex for parsing tapped Cask token to tap_constants

Fix locally failing `depends_on` test.

Refactor accessibility test.

Refactor Audit test.

Refactor DSL test.

Refactor Installer test.