* Update submodule pointer to be on v2.16.7 of Mbed TLS
* Update config file licenses
* Update readme.txt to include information on what Mbed TLS license the repo uses
* Removing FreeRTOS/Source in readiness for submoduling.
* Submoduling kernel.
* README.md update due to submoduling.
When releasing, please follow these steps:
1. in local directory, clean directory and check "git status" shows "nothing to commit, working tree clean" for ALL subdirectories.
2. copy source code and instructions only to an empty folder. Git related should not be in this folder -- this covers .git, .gitignore, .github, .gitmodules, gitmessages, ......
3. zip the folder from step 2. (create both .zip and .7z)
4. attach .zip and .7z to the release. (e.g. attach these two in new release -- https://github.com/FreeRTOS/FreeRTOS/releases/new)
5. PLEASE download both, unzip, diff with your local git repo. (should not see any difference other than git related.) And, sanity check a couple of projects.
