rewrite gpu/device/vec_math.hpp file 

old version isn't compiled with CUDA 5.5
new version doesn't depend on functional.hpp
fixed BroxOpticalFlow regression test

the output of BroxOpticalFlow differs a bit in CUDA 5.5
fixed BoxFilter sanity test (different rounding results)
fixed BroxOpticalFlow sanity test (increase epsilon value)

+ interpolateFrames and createOpticalFlowNeedleMap
Fix typo in .gitattributes.
fixed bug #3069 (infinite loop in GPU LBP Cascade detectMultiScale)
fix a bug(DetectorType never change)

changed line281 -> line220
Presentation:
because line 220 give the globle var mDetectorType,and in line 230 it will be compared with mDeteorType !!!  it will never be unequal ~
fix:
change mDetectorType(previous globle var) to a new local val tmpDetectorType
Merge pull request #890 from caorong:patch-1
Merge pull request #948 from jet47:cuda-5.5-support
Don't resolve symlinks when looking for modules.

We don't really need it, it makes the code longer, and it can lead to
inconsistent paths when OpenCV is itself inside a symlink.
Merge pull request #952 from SpecLad:jepg
Merge pull request #953 from jet47:fix-bug-3069
Merge pull request #955 from SpecLad:symlink