Merge pull request #1701 from MikeMcQuaid/deprecate-std-superenv-stuff

Library/Homebrew/compat.rb

Library/Homebrew/compat/ENV/shared.rb

Library/Homebrew/compat/ENV/std.rb

Library/Homebrew/compat/ENV/super.rb

Library/Homebrew/compat/macos.rb

Library/Homebrew/compilers.rb

Library/Homebrew/development_tools.rb

Library/Homebrew/extend/ENV/std.rb

Library/Homebrew/extend/ENV/super.rb

Library/Homebrew/extend/os/mac/development_tools.rb

Library/Homebrew/extend/os/mac/extend/ENV/super.rb

Library/Homebrew/os/mac.rb

Library/Homebrew/system_config.rb

Library/Homebrew/test/ENV_test.rb

Library/Homebrew/test/stdlib_test.rb