Naive impl. Slower than CPU
Optimized version. Faster than CPU
added tests
added documentation
moved documentation of BriefDescriptorExtractor to correct place
Fixed doc
Merge branch 'master' of https://github.com/Itseez/opencv into brief_cl
merge with upstream
Merge branch 'master' of https://github.com/Itseez/opencv into brief_cl
Merge branch 'master' of https://github.com/Itseez/opencv into brief_cl
Type conversions to fix warnings
Merge pull request #2027 from AD-530:brief_cl