New Cask: Adobe AIR Redistribution Helper

The Adobe AIR Redistribution Helper (ARH) utility is a small
executable that you can use as part of a custom installer. It can
perform many tasks such as detect the presence and version of an
installed AIR runtime as well as silently install AIR applications.
Merge pull request #3420 from vmrob/arh

New Cask: Adobe AIR Redistribution Helper