## Motivation
Introducing new models and features into OpenMMLab's algorithm libraries
has long been complained to be troublesome due to the rigorous
requirements on code quality, which could hinder the fast iteration of
SOTA models and might discourage potential contributors from sharing
their latest outcome here.
Ref: https://github.com/open-mmlab/mmsegmentation/pull/2412
## Modification
This PR adds a new `projects/` folder, which will be a place for some
experimental models/features. Implementations inside might be not quite
perfect but already fine to produce some exciting results. We hope that
this PR can help us better embrace the contribution from our community.
We also add the first example project to illustrate what we expect a
good project to have.
谢昕辰