Merge pull request Homebrew#2631 from GauthamGoli/audit_homepage_rubocop

audit: Port audit_homepage method to rubocop and add tests

Merge pull request Homebrew#2571 from danielmartin/revert-2517-fix-se…

…lect-blocking

Revert "Fix `IO#select` blocking."

Merge pull request Homebrew#2446 from mansimarkaur/diagnostic_tests

[WIP] Added test for check_access_lock_dir

Merge pull request Homebrew#2412 from EricFromCanada/master

Xcode: update supported versions & download URLs for 8.3

Merge pull request Homebrew#2282 from reitermarkus/cask-versions-string

Make `timestamped_versions` return an array of strings.

Merge pull request Homebrew#2013 from reitermarkus/spec-hardware

Convert Hardware test to spec.

Merge pull request Homebrew#1931 from MikeMcQuaid/update-performs-mig…

…rations

update: note migrations may be performed.

Merge pull request Homebrew#1894 from reitermarkus/appcast-checkpoint

Add internal command to calculate appcast checkpoint.

Merge pull request Homebrew#1806 from MikeMcQuaid/audit-virtualenv-se…

…tuptools

audit: check virtualenv and setuptools resource.

Merge pull request Homebrew#1768 from MikeMcQuaid/deprecate-homebrew-…

…versions-devel-only

Deprecate Homebrew/versions, Homebrew/devel-only.