extended universal intrinsics: added 64-bit integers, improved shift operators, renamed "pack" operations; changed semantics of extended integer multiplication, added v_dotprod.
also, split intrinsics into separate files. C implementation is compiled only when none of SSE2 or NEON is available.

HAL extensions: added initial version of universal intrinsics (C implementation and SSE2, NEON - TBD). added empty files where some functionality from core and imgproc will be moved to

2. Algorithm::load/save added (moved from StatModel)
3. copyrights updated; added copyright/licensing info for ffmpeg
4. some warnings from Xcode 6.x are fixed

work_var_count and sample_count are both 32bit integer, if the product of work_var_count and sample_count is bigger than 2^31, the compiler will treat (work_var_count*sample_count) as a negative number. Force work_var_count as an unsigned 64bit integer to avoid this issue.

Jpeg2k color to greyscale conversion on non-Windows is done post decoding because system libjasper segfaults when decoding color images as greyscale.

On Windows, the tmpnam function returns a temp filename in the current directory, which has a prepended backslash '\\'.
This subsequently fails the open function.

This patch creates a proper temp filename in the temp folder and makes unlike work by opening the file as short-lived.

small formatting fixes