[Gm2] latest git commits

[Gaius Mulley]

Hi,

I've added getopt.def and GetOpt.def/mod to the gcc-6.4.0 branch,
gcc-5.4.0 branch and gcc-master branch.  Also added the ability to pass
objects to the gm2 linker on the command line.  The gm2 driver will only
include objects not present on the command line to avoid duplicates.
No extra regression failures are seen.

I'm in the process of building a new debian stretch package (based on
gcc-6.4.0) which should be uploaded onto floppsie tomorrow,

regards,
Gaius