Initial implementation of xIntensity and RawIntensity

Include these two command line parameters implemented from Kalroth and
sgminer.  xIntensity will not be terribly useful for cards with a high
number of shaders.  RawIntensity will be useful for any card though -
Use in multiples of 64 on older cards, multiples of 32 & 16 appear to
work on R7 cards
xIntensity MIN & MAX variable usage

put the variables where they belong in place of the hard coded numbers
cgminer to yacminer in interface

replace a couple instances of cgminer with YACMiner
Remove error on specifying kernel with scrypt

change the config file name as well.
Fix GPU_FAN to max when it's never been set

Add define for hard-coded constant.  When writing config, if the gpu_fan
matches that constant and write 0 instead.  without setting this
parameter, and saving a conf file and reloading it, the GPU fan would
spin to max, but not be under fan control and would never slow down.