refactored gpu::LUT function:

* converted it to Algorithm, because implementation uses inner buffers and
  requires preprocessing step
* new implementation splits preprocessing and transform,
  what is more effecient
* old API still can be used for source compatibility
* new implementation works only with CUDA 5.0
switched to Input/Output Array in gpu::copyMakeBorder
switched to Input/Output Array in reductions operations
refactored gpu::gemm function:

* converted it to Algorithm
* old API still can be used for source compatibility