Switch to main

Relates to #194 (closed)

Switching over to use main. This MR will target the master branch, but upon merge, a new branch should be created in the project called main using the updated master as its source. The new branch must then be:

• Set as default branch
• Protected
  • Developers and Maintainers may merge
  • Maintainers may push
  • Force push disabled

All developer forks must be similarly updated to set main as the new default branch and protected.

Finally, the master branch in the upstream repository should be modified such that it remains protected, but "No one" may merge and "No one" may push. It is important to keep the master branch available because some older documentation links to some files in this branch directly and this documentation cannot be updated.

The master branch in developer forks may be deleted.

Important

Upon merge, any other open merge requests targeting the master branch must be updated to target the main branch. Future merge requests should be opened targeting the main branch.

/cc @jdbrown @ehunter @eklatzco @khaynie