blockNorm computation is done CUDA-side

The original block normalization step looped over (x, y). It launched 4 groups of nested-loops:
+ Evaluate blockNorm based on h
+ Compute block[][][]
+ Evaluate blockNorm based on block[][][]
+ Compute descriptorVector

The first group has been moved to its CUDA implementation.
The others will be moved to CUDA in order to get an efficient CUDA implementation for 'block normalization'.
Merge branch 'cuda_hog' into cuda_hog_fullcuda
cudaErrorCheck_goto on cudaThreadSynchronize() calls
`block` computation done CUDA-side

CUDA-version uses the same behaviour as the one in use in the branch `hog_bug`
For that reason, its output needs to be compared with the appropriate C-version
Merge branch 'hog_bug' into cuda_hog_fullcuda
Bug fixed: missing square-root in DalalTriggsHOGdescriptor_compute_block
Computation of blockNorm based on d_block done CUDA-side
Free d_h memory as soon as possible
Computation of descriptorVector done CUDA-side
Remove unecessary variables
BUG fixed: Missing syncthreads after cache initialisation (blockNorm)
Merge commit '8334fb2' into cuda_hog_fullcuda
Bug fixed: Misspelled parameter name
Merge commit 'c10b075' into cuda_hog_fullcuda

Conflicts:
	menpo/image/feature/cu/HOG.cu
Merge branch 'cuda_hog' into cuda_hog_fullcuda

Conflicts:
	menpo/image/feature/cu/HOG.cu
CUDA vectors allocated only once by call to DalalTriggs
Merge branch 'cuda_hog' into cuda_hog_fullcuda

Conflicts:
	menpo/image/feature/cu/HOG.cu
descriptorVector occurences have been replaced by outputImage

This new version replaces all occurences to descriptorVector by occurences to outputImage.
It saves one cudaMemcpy per window and should give a little speed-up for computations on windows.
Merge branch 'cuda_hog' into cuda_hog_fullcuda

Conflicts:
	menpo/image/feature/cu/HOG.cu
Merge branch 'cuda_hog' into cuda_hog_fullcuda

Conflicts:
	menpo/image/feature/cu/HOG.cu