Feature Request: Stitching API

### Stitching API

Opencv provide a Stitching module/API

Bascially, i would like to be able to rewrite [stitching_detailed.cpp](https://github.com/opencv/opencv/blob/3.4/samples/cpp/stitching_detailed.cpp) in javascript

This includes :
* [Stitcher](https://docs.opencv.org/3.4/d2/d8d/classcv_1_1Stitcher.html) class
* Features extractors (already implemented in opencv4nodejs)
* Estimators class : [AffineBasedEstimator](https://docs.opencv.org/3.4/d0/df2/classcv_1_1detail_1_1AffineBasedEstimator.html) class and [HomographyBasedEstimator](https://docs.opencv.org/3.4/db/d3e/classcv_1_1detail_1_1HomographyBasedEstimator.html#a1721c1881d881d337c7ffb1615ac508c) class
* [AffineBestOf2NearestMatcher](https://docs.opencv.org/3.4/d3/dda/classcv_1_1detail_1_1AffineBestOf2NearestMatcher.html), [BestOf2NearestMatcher](https://docs.opencv.org/3.4/d3/dda/classcv_1_1detail_1_1AffineBestOf2NearestMatcher.html), [BestOf2NearestRangeMatcher](https://docs.opencv.org/3.4/d8/d72/classcv_1_1detail_1_1BestOf2NearestRangeMatcher.html)
* [BundleAdjusterReproj](https://docs.opencv.org/3.4/dc/d54/classcv_1_1detail_1_1BundleAdjusterReproj.html), [BundleAdjusterRay](https://docs.opencv.org/3.4/da/d7c/classcv_1_1detail_1_1BundleAdjusterRay.html) ...
* [Wrappers](https://docs.opencv.org/3.4/d0/dfa/group__stitching__warp.html) (PlaneWarper, FisheyeWarper, CylindricalWarper, AffineWarper, StereographicWarper, CompressedRectilinearWarper, RotationWarper ...)
* [MultiBandBlender](https://docs.opencv.org/3.4/d5/d4b/classcv_1_1detail_1_1MultiBandBlender.html), [FeatherBlender](https://docs.opencv.org/3.4/d4/d69/classcv_1_1detail_1_1FeatherBlender.html)

## Next steps

This looks like a huge amount of work, is there anybody else interested ?