Pytorch-segmentation-models-trainer

- Bug fixes on mask building;
- Bug fixes on detection model training.
- New mode on build masks;

- Minor improvements on polygonization methods;
- Inference server added;

- Gradient Centralization added;

- Object Detection added;
- Instance Segmentation added;

- PolygonRNN model added;
- Added the option of choosing the number of images on ImageCallback;
- Added the option of adding created masks to existing csv;
- Added the option of generating bounding boxes in create masks;
- Added the option of converting csv dataset to coco dataset;

- Fixes on requirements;