Cudaarithm python bindings for merge and split are inconsistent with the format…

Cudaarithm python bindings for merge and split are inconsistent with the format of existing cuda python functions.  Split does not return its output and merg's documentation is incorrect.

modules/cudaarithm/include/opencv2/cudaarithm.hpp

@@ -438,7 +438,7 @@ CV_EXPORTS_W void polarToCart(InputArray magnitude, InputArray angle, OutputArra
 
 @sa merge
  */
-CV_EXPORTS_W void merge(const GpuMat* src, size_t n, OutputArray dst, Stream& stream = Stream::Null());
+CV_EXPORTS void merge(const GpuMat* src, size_t n, OutputArray dst, Stream& stream = Stream::Null());
 /** @overload */
 CV_EXPORTS_W void merge(const std::vector<GpuMat>& src, OutputArray dst, Stream& stream = Stream::Null());
 
@@ -450,9 +450,9 @@ CV_EXPORTS_W void merge(const std::vector<GpuMat>& src, OutputArray dst, Stream&
 
 @sa split
  */
-CV_EXPORTS_W void split(InputArray src, GpuMat* dst, Stream& stream = Stream::Null());
+CV_EXPORTS void split(InputArray src, GpuMat* dst, Stream& stream = Stream::Null());
 /** @overload */
-CV_EXPORTS_W void split(InputArray src, std::vector<GpuMat>& dst, Stream& stream = Stream::Null());
+CV_EXPORTS_W void split(InputArray src, CV_OUT std::vector<GpuMat>& dst, Stream& stream = Stream::Null());
 
 /** @brief Transposes a matrix.