build: improve packaging (#249)

PR to make to make packaging a little nicer, in line with how packaging
works in `unstructured`. In particular, support for extras is added.

This consists of:
- Adding the file `sg.in` for dependencies related to `supergradients`.
This file has been `pip-compile`d with output `sg.txt`.
- All dependencies have been `pip-compile`d.
- Adding the file `constraints.in` to add a `numpy` constraint that is
required for compliance with `supergradients`. Dependencies that precede
`sg.in` need to know about this to avoid conflicts. `constraints.in` is
added as a constraints file for all other dependency files.
- `make` targets are added for installing `supergradients` dependencies.
- CI is updated to install `supergradients` dependencies.
- `supergradients` extra is added to `setup.py` and `MANIFEST.in` so it
can be picked up by PyPi.
- To support the fact that the `supergradients` dependencies are not
guaranteed to be installed, the way imports are handled in the
`super_gradients.py` model file has been changed so imports are only
attempted in the model constructor, in a module-level global variable.
The constructor was used instead of doing the import in `initialize` due
to an error that occurred during import when initiated from
`initialize`.

Author: qued

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.7.5
+
+* Improved packaging
+
 ## 0.7.4
 
 * Dynamic beam search size has been implemented for Chipper, the decoding process starts with a size = 1 and changes to size = 3 if repetitions appear.

MANIFEST.in

@@ -1 +1,2 @@
 include requirements/base.in
+include requirements/sg.in

Makefile

@@ -19,10 +19,10 @@ install-base: install-base-pip-packages
 
 ## install:                 installs all test, dev, and experimental requirements
 .PHONY: install
-install: install-base-pip-packages install-dev install-detectron2
+install: install-base-pip-packages install-dev install-sg install-detectron2
 
 .PHONY: install-ci
-install-ci: install-base-pip-packages install-test install-paddleocr
+install-ci: install-base-pip-packages install-test install-sg install-paddleocr
 
 .PHONY: install-base-pip-packages
 install-base-pip-packages:
@@ -46,6 +46,10 @@ install-test: install-base
 install-dev: install-test
 	pip install -r requirements/dev.txt
 
+.PHONY: install-sg
+install-sg: install-base
+	pip install -r requirements/sg.txt
+
 ## pip-compile:             compiles all base/dev/test requirements
 .PHONY: pip-compile
 pip-compile:
@@ -56,6 +60,7 @@ pip-compile:
 	sed 's/^detectron2 @/# detectron2 @/g' requirements/base.txt
 	pip-compile --upgrade requirements/test.in
 	pip-compile --upgrade requirements/dev.in
+	pip-compile --upgrade requirements/sg.in
 
 
 #################

requirements/base.in

@@ -1,9 +1,8 @@
+-c constraints.in
 layoutparser[layoutmodels,tesseract]
 python-multipart
 huggingface-hub
 opencv-python!=4.7.0.68
-super-gradients
-supervision
 # NOTE(benjamin): Pinned because onnxruntime changed the way quantization is done, and we need to update our code to support it
 onnxruntime<1.16
 # NOTE(alan): Pinned because this is when the most recent module we import appeared