Requirement#modify_build_environment may depend on the side effects of
Requirement#satisfied?, so make sure the latter is called at least once
for each requirement during formula installation. Prior to b70b5429,
Requirement#satisfied? would usually be called during Build#expand_reqs,
but that is longer the case.

rubocop: don't always display cop names.

fix broken sentence

formula: reject dot dirs as racks

pathname: fix rmdir_if_possible with mount points

Deprecation fixes and cleanup

utils: no deprecations for cached formulae.

These are already present in compat.

`HOMEBREW_CACHE`d and `.brew`ed formulae cannot be updated so don't
complain about their deprecation.

Dot directories are not racks because formulae names do not start with
"." so avoid attempting to descend into dot directories, which may not
always be possible (e.g. .Trashes).

Attempting to rmdir a directory that is a mount point results in EBUSY,
not EACCES or ENOENT, so also rescue EBUSY in rmdir_if_possible.

docs/Versions: versions should build.

Seems obvious but was somehow omitted.

Versions: update acceptable versioned formulae.

Clarify further what's acceptable and what isn't.

README.md: secure two URLs

`prepend` instead of alias hacks for deprecations

It took me a while to figure out what this deprecation actually did,
because the message wasn't accurate.

We should probably write tests for these going forward. ;)

README: update list of maintainers

Deprecate default_formula Requirement DSL

cask bash completion: have upgrade only complete outdated packages

publish_bottle_file_on_bintray: Use f.full_name

Disable and add more deprecations.

info: show spec options for optionless formulae

Deprecate requirements harder

rubocop 0.52.1

Formula-Cookbook: various updates.

These have all been deprecated/compat for a while.