chore: update readme, example config, and running documentation

Co-authored-by: asleepyskye <skye@vixen.lgbt>

dev-docs/BRANCHRENAME.md

@@ -0,0 +1,18 @@
+On 2020-06-22, we renamed the `master` branch to `main`. 
+
+This should mean very little, but if you have existing clones,
+you'll need to update the branch references, like so:
+
+1. **Fetch the latest branches from the remote:**  
+`$ git fetch --all`
+2. **Update the upstream remote's HEAD**  
+`$ git remote set-head origin -a`
+3. **Switch your local branch to track the new remote**  
+`$ git branch --set-upstream-to origin/main`
+4. **Rename your branch locally**  
+`$ git branch -m master main`
+
+(steps from https://dev.to/rhymu8354/git-renaming-the-master-branch-137b)
+
+The `master` branch was fully deleted on 2020-07-28.
+If you get an error on pull on an old clone, that's why. The commands above should still work, though.