freeimage: Correctly handle saving uint16 images (closes gh-1101)
Merge pull request #1102 from stefanv/bug/freeimage_uint16

freeimage: Correctly handle saving uint16 images (closes gh-1101)
Fix bugs in HOG
Replaced convolve1d by ad-hoc gradient computation
Code valid for all image dtypes
Minor fix
Merge pull request #1105 from pmneila/master

Minor fix for bugs in HOG implementation