Log Message:
Initial import of gcc49-4.9.1 as lang/gcc49.

Changes, New Features, and Fixes in GCC 4.9 can be found here:

  https://gcc.gnu.org/gcc-4.9/changes.html

This is based heavily on lang/gcc47 but updated for GCC 4.9.1.  Tested on
SmartOS (32-bit and 64-bit) and NetBSD 6.1.4/amd64.