Sometimes, pkgutil will return actual files (usually .nib files) as if they were part of the directory.  Microsoft Office is an example of this: in a recent update the file `/Library/Application Support/Microsoft/MAU2.0/Microsoft AutoUpdate.app/Contents/SharedSupport/Microsoft Error Reporting.app/Contents/Resources/en.lproj/MainWindowAlt.nib` was returning from `/usr/sbin/pkgutil --only-dirs --files com.microsoft.package.component` even though it should have been a file instead of a directory.  This caused the `rmdir` command to fail.

This patch will check if we are trying to delete a “directory” that is really a “file” - and if we are, we just delete the file instead.  This will allow packages that get in this state to be uninstalled.  A unit test which can be run using `brew cask-tests` is also included.

brew deps: support --full-name in --installed, --all, and --tree modes

diagnostic: check for bad tap files.

create: remove :x11 dep from new formula template

bump-formula-pr: fix removal of old mirrors

brew create: add meson support

Updated homepage 404 check to use explicit parameters and return the …

Previously, old mirrors are only removed if the requested spec is
stable, and if the mirror lines only have two leading spaces. This leads
to stale mirror line(s) when the formula a stable block like

    stable do
      url "http://example.com/v1.0.tar.gz"
      mirror "http://example.net/v1.0.tar.gz"
    end

where the mirror line is lead by four spaces.

In this commit, we discard the /(^ mirror .*\n)?/ pattern, and instead
create a pattern with the exact url and flexible leading spaces for each
mirror of the requested spec.

audit: handle a nil revision map.

Deprecate 32-bit options.

Remove Xcode prerelease warnings.

These were formerly supported but as it has been a very long time since
32-bit software was necessary on macOS these have been deprecated with
a `brew audit` warning and a future `odeprecated`.

update-reset: add new command.

postinstall: don't allow writes to prefix itself.

super/cc: loosen cellar formula regex.

meson is quickly gaining popularity as build system, in combination with
ninja. Several Gnome projects for example are currently transitioning
from autotools to meson, mostly because it allows for Visual Studio
builds, which is impossible to accomplish with autotools.

In order to facilitate generating meson based Formulas, I added support
for meson to brew-create.

At this point we probably do want to know about issues that crop up in
betas so we can fix them before the new version of Xcode is released.
Additionally, this doesn't really work well any more with our new
tag-based workflow as it means we need to cut a new tag immediately
after a new Xcode is released.

audit: don't allow use of OS.mac?/OS.linux?.

Never trigger too old CLT check on <10.7.

While we fake a CLT for these versions they never shipped with the CLT
so cannot update it.

Forbid their use in Homebrew/core which only supports macOS. This may
be added to more/all official taps in future.

Add new `brew update-reset` command to provide a helpful troubleshooting
fallback to fetch and reset all repositories. This could have lived in
`brew update` but it makes sense to avoid the complexity of sharing
logic between these scripts and keeping this one simpler.

create: handle Version::NULL correctly.

Fixes #1688.

diagnostic: check for multiple Cellars.

audit: flag use of "fails_with :llvm".

prune: don't remove top-level directories.

which_all: don't assume path is a string.

Tweak issue template and contributing guidelines.

Fix error message when cask fails to install.

fix typo

Match HOMEBREW_TAP_FORMULA_REGEX to avoid skipping valid cellar regexes.

formulary: call tap not formula