basic mutiGPU version, trying not to interfere the future stream part
add time measure
add -lpthread flag
Oops, forget to add cudaSetDevice...
apply to multiGPU method on decoding
Merge remote branch 'origin/multiGPU'

Conflicts:
	src/Makefile.in
	src/decode.cu
	src/encode.cu
update header files
add Makefile.in