fix compile on linux environment

Changed include path to <CL/opencl.h>.
Removed unsupported ChannelOrder and ChannelDataType.
drop terminating zero from info strings
fix program build

* Set correct number of devices.
* Check build log only on program failure (?).
add deprecated clCreateImage2D for compatiblity with OpenCL 1.0, 1.1
Merge branch 'master' into linux