Initial GPU integration.
Add GPU tests to own directory.
Merge branch 'next' into gpu

Conflicts:
	tests/tests/Makefile
Merge branch 'next' into gpu
Fix some bux with GPUs
move events to GPU
Merge branch 'next' into gpu

Conflicts:
	tests/tests/Makefile
add GPU tests, modify gpu tests
update README
Merge branch 'gpu' of https://github.com/LenaO/GPI-2 into lena
Merge branch 'lena' into gpu
Remove dependencies in Makefile.
Clean make includes files.
Merge branch 'next' into gpu
Merge branch 'next' into gpu
Merge branch 'next' into gpu
Small clean-up to gpu testcases.
Allow support for allreduce with GPU Pointers
Merge branch 'gpu' of https://github.com/cc-hpc-itwm/GPI-2 into gpu

Conflicts:
	tests/make.defines
	tests/tests/Makefile