Details:
- Added various micro-kernels for the following architectures:
Intel MIC
IBM BG/Q
IBM Power7
AMD Piledriver
Loogson 3A
and reorganized kernels directory. Thanks to Tyler Smith, Mike Kistler,
and Xianyi Zhang for contributing these kernels.
- Added configurations corresponding to above architectures, and renamed
"clarksville" configuration to "dunnington".
