Looks like we don't actually use them; when creating precompiled headers
with Visual C++, a dummy .cpp is created at build time.

ReST directive was used. Also fixed some other ReST directives that were
not correct and removed some warnings during buildbot checks.

- Used lunix style slashes - works on most systems
- Removed all trailing whitespaces

This should allow many algorithms to take advantage of more parallelization
technologies.

Also cv::, cv::gpu:: and cv::ocl:: namespace prefixes can be safely omitted
inside CV_ENUM and CV_FLAGS

Issues #2646

updated patch for tests; reenabled SURF & Denoising; removed fixes in ocl tests, since this is already fixed in another pull request

All errors were found by doc/check_docs2.py

* reorder arguments
* rewrite accuracy tests
* replace doubles with integer arithmetic inside the main loop

All the functions from it are moved to the header
opencv2/photo/photo.hpp

enabled SSE3 by default; integrated SSE3-optimized bilateral filter (by Grigoriy Frolov); modified API of non-local means (use Input/OutputArrays)