Unnfortunately, we maintain 2 copies of documentation images (one
for the documentation source; another for the generated documentation).
We need to solve this as it makes the repository size unproportionally
large.

Add missing image files [arghhhh.]

Add missing files :-(

* Asymmetric post-training quantization (only symmetric supported so until now)
* Quantization aware training for range-based (min-max) symmetric and asymmetric quantization
* Per-channel quantization support in both training and post-training
* Added tests and examples
* Updated documentation

* Implemented as a Policy
* Integrated in image classification sample
* Updated docs and README