jetty76 7.6.16

Closes #562.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
gcc49 4.9.2

 - don't rename libiberty.h, see
   Homebrew/homebrew@b84ec7be94cbb7b63ffd14ab16335cea93f4a38f
ruby193 1.9.3-p551
ruby20 2.0.0-p598
gcc4[3-9]: blacklist llvm-gcc

Fixes Homebrew/homebrew#34222.