Merge pull request #1 from Realeyes/master

Replace PENCIL std library headers with generated versions.
Avoid CL_INVALID_HOST_PTR when creating buffer

OpenCL's clCreateBuffer requires the host pointer argument to be NULL
when the CL_MEM_COPY_HOST_PTR or CL_MEM_USE_HOST_PTR flag is not given.
Our function opencl_create_device_buffer accepts a host pointer, to
catch pencil_alloced buffers.  It should not pass that pointer to
clCreateBuffer if neither of the aforementioned flags is given.
Merge pull request #2 from Realeyes/master

Add most OpenCL functions
Take ARCH into account when building runtime.
Include pencil_lib.h from pencil_compat.h

Suggested by Albert.  Having only one header file for the PENCIL
compatibility mode is better than having two files (in case a user wants
only to use PENCIL in compatibility mode, i.e. to compile his code with
a standard C compiler).  This patch includes the automatically
generated pencil_lib.h file in pencil_compat.h so that the user
does not need to think about including both.
Merge pull request #3 from rbaghdadi/fixes

Include pencil_lib.h from pencil_compat.h
Fix __pencil_maybe and __pencil_assert in compatibility mode
Merge pull request #4 from rbaghdadi/fixe_compatibility

Fix __pencil_maybe and __pencil_assert in compatibility mode
Merge remote-tracking branch 'carp/master'