added a 'silent' arg to make_kernels that by default disables echoing the nvcc calls to stdout. Error logging to stderr is not affected.
added a 'silent' arg to make_kernels that by default disables echoing the nvcc calls to stdout. Error logging to stderr is not affected.

nhynes/neon,dongjoon-hyun/neon,coufon/neon-distributed,Jokeren/neon,Jokeren/neon,Bam4d/neon,coufon/neon-distributed,dongjoon-hyun/neon,Jokeren/neon,dongjoon-hyun/neon,DougFirErickson/neon,nhynes/neon,DougFirErickson/neon,coufon/neon-distributed,NervanaSystems/neon,Bam4d/neon,NervanaSystems/neon,Bam4d/neon,NervanaSystems/neon,DougFirErickson/neon,Jokeren/neon,NervanaSystems/neon,nhynes/neon