SRM implementation with correct formating

[dheer-prog]

Feature Implemented

The following code implements Statistical Region Merging based segmentation as detailed in this paper
R. Nock and F. Nielsen, "Statistical region merging," in IEEE Transactions
on Pattern Analysis and Machine Intelligence, vol. 26, no. 11

Files added and changed

Added srm.cpp this contains the core implementation for the segmentation,
test_srm.cpp this contains the test code to check the function working
segmentation.hpp this contains the base class for the new implementation

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under Apache 2 License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
• The PR is proposed to the proper branch
• There is a reference to the original bug report and related work
• [x ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake

[dheer-prog]

@asmorkalov, I changed this pr from 4.x to 5.x as this is a new feature

[dheer-prog]

Hello @asmorkalov this build seems to be failing on this particulart test case
perf_wechat_qrcode ; cases (tests): 3 (50) ; passed: 25 ; failed: 25 ; failed
But this and the other related PR's(#4157) don't have anything to do with that module I think there is something wrong in the test builds process