ENH: Modularize cmake code for GT.M and Cache specific setup

Separated GT.M and Cache specific setups to different cmake
configuration files.

And converge to using "VENDOR_NAME" instead of "VENDER_NAME"

OSEHRA-Id: http://issues.osehra.org/browse/OAT-76
Change-Id: Ie7a111f39d06b4bdb634fd67f7ad2e53ac7d1148
Merge "ENH: Modularize cmake code for GT.M and Cache specific setup"