Test all GPUs by default
Test all GPUs by default

Fixes issue #21

mohamed-ali/thrust,zeryx/thrust,egaburov/thrust,xiongzhanblake/thrust,marksantos/thrust,raygit/thrust,thrust/thrust,xiongzhanblake/thrust_src,egaburov/thrust,dachziegel/thrust,xiongzhanblake/thrust,dachziegel/thrust,sarvex/thrust,thrust/thrust,egaburov/thrust,jaredhoberock/thrust,mohamed-ali/thrust,arnabgho/thrust,mohamed-ali/thrust,thrust/thrust,andrewcorrigan/thrust-multi-permutation-iterator,sarvex/thrust,sdalton1/thrust,jaredhoberock/thrust,xiongzhanblake/thrust_src,sdalton1/thrust,jaredhoberock/thrust,raygit/thrust,xiongzhanblake/thrust_src,andrewcorrigan/thrust-multi-permutation-iterator,zeryx/thrust,thvasilo/thrust,marksantos/thrust,zhenglaizhang/thrust,dachziegel/thrust,thvasilo/thrust,marksantos/thrust,sarvex/thrust,thrust/thrust,jaredhoberock/thrust,arnabgho/thrust,zeryx/thrust,Ricardo666666/thrust,zhenglaizhang/thrust,raygit/thrust,Ricardo666666/thrust,GrimDerp/thrust,andrewcorrigan/thrust-multi-permutation-iterator,GrimDerp/thrust,thrust/thrust,xiongzhanblake/thrust,jaredhoberock/thrust,Ricardo666666/thrust,arnabgho/thrust,sdalton1/thrust,zhenglaizhang/thrust,thvasilo/thrust,GrimDerp/thrust