Print a better exception message and handle this in more cases rather
than producing confusing errors when it’s unset.

bin/brew: improve $HOMEBREW_REPOSITORY/bin/brew handling.

brew.sh: don't require /usr/local/Cellar creation.

update-report: also link `brew*.1` manpages.

Merge Cask’s `Pathname` extension with Homebrew’s.

Add vendored `plist` to ReadMe.

Otherwise if your `HOMEBREW_PREFIX` and `HOMEBREW_REPOSITORY` are not
equal then your tap manpages will be linked but your `brew*` ones will
not.

If `/usr/local` is the prefix but not the repository (so bottles can be
used) then running `/usr/local/bin/brew` works great but
`$HOMEBREW_REPOSITORY/bin/brew` assumes the prefix is
`$HOMEBREW_REPOSITORY`. This is a pain when doing work on the Homebrew
repository and having e.g. `bin` in your `$PATH`. Improve this
behaviour so `bin/brew` knows how to handle this situation.

This will enable this code to be reused in a future commit and makes it
more obvious what’s being done.

The previous approach of trying to do it on one line was confusing.

If you're using e.g. a `/usr/local/homebrew` prefix then don't require
the `/usr/local/Cellar` to be manually created to avoid e.g.
`/usr/local/homebrew/Cellar` being used. Let's do all we can to let
people use this `Cellar` location as it means they can put their
repository wherever they like and still use all our bottles.

Enable ruby-macho by default.

update: make GIT_EXECUTABLE an absolute path.

Move Cask’s vendored `plist` to `Homebrew/vendor`.

Make -no_weak_imports opt-in.

Revert "diagnostic: ignore duplicated `brew-cask` commands"

The experiment to add `-no_weak_imports` unconditionally has been a bit
of a failure. It's broken more than it's fixed and I don't think we can
have this as a default for Xcode 8.

Add `ENV.no_weak_imports` to be used by formulae authors and make
`ENV.no_weak_imports a no-op (for now).

We may reconsider this behaviour in future.

Otherwise it can end up as e.g. `bin/git` which then breaks when we
`cd` to another directory and try to run it.

Forgot renaming `cab-container`.

Cask Refactoring

Add atom language plugin to docs

Refactor `shutup`.

add .editorconfig