mscash2-opencl honours LWS and GWS env variables, des-opencl and bf-opencl
honours GWS environment variables, added functions to detect optimal GWS
for bf-opencl and des-opencl

Conflicts:
	src/common_opencl_pbkdf2.c
	src/opencl_DES_fmt.c
	src/opencl_mscash2_fmt.c
Fix for clock err in timers.
Fix SAVE= timer similar to Costin's patch.