- `--embeddded` mode is the now the default
- embedded cache and ports is also the default
- emsdk now fully polulates the cache by default so no need to do that.
- always "activate" the SDK avoiding that need things to work without
that.
- avoid making extra symlinks.
- remove python2
Dockerfile:
- Use the most recent stable debian (buster) instead of the previous one
- Build version 1.39.11 by default instead of 1.38.43
- Fix small typo in the comments
Makefile and README.MD: Fix incorrect name of image on dockerhub.