this allows odd linux installations (Android) to function

upgrade: make pinned error have correct exit code.

Don't use Linuxbrew/homebrew-core (yet, at least).

Also, display before saying "no packages to upgrade".

Fixes #3936.

This can't be tapped on vanilla Homebrew/brew because things like e.g.
`GlibcRequirement` are missing. We will put this back when the Linuxbrew
to Homebrew migration is complete.

install: add --include-test option.

Improve external command documentation

deps: don't display recursive test dependencies.

Extract `brew bundle` and `brew services` docs from their help. Add a
little for `brew cask` until we can think about e.g. merging the
manpages.

Allow at `install` (or `install --only-dependencies`) time to specify
that test dependencies should be installed. This will allow simplifying
code in `brew test-bot`.

This could also be made an environment variable if desired by
maintainers.

append ? to git_remote_exists

add ? to svn_remote_exists

Update `rubocop-cask` to 0.17.3.

You only care about the test dependencies for the specific formula you
are testing right now.

cleanup: fix removing lock files on NFS

If the underneath file system is a Network File System,
`brew cleanup` will fail to remove the lock files with following error
message:

Error: Bad file descriptor @ rb_file_flock - /path/to/the/lock_file

This commit fixes such issue and adds the corresponding test case.

install: make --only-dependencies fill in missing.

This makes the `brew install --only-dependencies` command more useful by
filling in missing dependencies for a formula even if it's already
installed.

build: do not skip runtime deps of buildtime deps

Fix #3883
Revert 2fb5ead3

utils/git: use exact format for last_revision_*

upgrade: add HOMEBREW_UPGRADE_CLEANUP variable.

Format for oneline can be overridden in user's gitconfig. If that's the
case, last_revision_commit_of_file won't work properly, and because of
that last_revision_of_file won't work at all.

Here's what I was getting when running brew tests:

       expected: "6bec2de"
            got: "\e[33m6bec2dee633f\e[m"

I have abbrev length set to 12, and oneline formatting is more colorful.

So, instead of relying on overrideable format, it should rather specify
"--format=%h" to get only hash, and speciy --abbrev=7 to force abbrev
length to be 7

After this commit tests are passing for me.

Allow users to specify they want `brew upgrade --cleanup` to always be
run when they run `brew upgrade`.

Fix style in `brew create`-generated formulae

- Fix indentation oddities
- Add empty lines where we expect them in submitted formulae

utils: check for tap_message in odeprecated.

`tap` is not a method-wide variable.

Fixes #3907

upgrade: fix the man page wrongly saying that it will upgrade pins.

This is incorrect as in order to upgrade a pinned package it must
first be unpinned.

Homebrew-and-Python: update binary locations.

Updated to comply with PEP 394:
https://www.python.org/dev/peps/pep-0394/

virtualenv_install_with_resources: invoke python with versioned name.

The unversioned python executable no longer refers to python3.

diagnostic: remove python pth check.

This isn't an issue with Homebrew but an issue for users to configure
themselves. It's also nonsensical with current Python configurations
e.g. https://discourse.brew.sh/t/brew-doctor-warnings-about-python-3-6-site-packages-and-sitecustomize/1805/1