Sporadically people ask to whitelist doctor warnings or file issues when
there's nothing actually wrong. Help reassure such people with a
friendly message.

Closes Homebrew/homebrew#30230.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

In Play 2.3 the play command has become the activator command. Play has
been updated to use Activator.

People should use typesafe-activator formula instead.

You can read more about this change at:
http://www.playframework.com/documentation/2.3.x/Migration23
and
http://www.playframework.com/documentation/2.3.x/Highlights23



Closes Homebrew/homebrew#30262.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Both build environments remove MACOSX_DEPLOYMENT_TARGET by default.

Fixes Homebrew/homebrew#30204.
Closes Homebrew/homebrew#30217.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Closes Homebrew/homebrew#30028.

Fixes Homebrew/homebrew#30212.

Does not compile with modern compilers and has not been updated
since 2008.

Closes Homebrew/homebrew#30040.

Fixes Homebrew/homebrew#30084.
Closes Homebrew/homebrew#30203.

Unlike CompilerFailure, the interface of Compiler is entirely internal,
so we don't need to maintain compatibility with anything.