update version and versioning documentation

VERSIONING.md

@@ -4,23 +4,17 @@ We use the following versioning design compatible with
 <https://www.python.org/dev/peps/pep-0440/>.
 
 - Always zero-index.
-- Versions are tracked in `pretext/static/VERSION` (to be imported by both `setup.py` and the CLI itself for display)
-- We use `[Major].[Minor]` versioning (with implied `.0` bugfix suffix), whose history is kept in the `master` branch.
-  - If we discover we need to bugfix a minor release, we create a branch `[Major].[Minor].(N+1)` to fix things and publish the new version, and eventually merge these changes back into `master` for release in `[Major].[Minor+1]`.
-- Each version always has at least one release candidate `rc0` for preview. If `rcN` reveals more work and a new preview is needed, `rc(N+1)` is developed. Otherwise a new commit removing the `rcN` is made (this should be the only change from `rcN` to the public release).
-- The final commit of a particular release candidate or public release is `git tag`'d as that version and should reflect what's on PyPI.
-
-An illustration of our version history looks something like this:
-
-```
-0.0rc0 (untagged) (several unpublished commits)
-0.0rc0 (tagged) (one commit, published, further work needed)
-0.0rc1 (untagged) (several unpublished commits)
-0.0rc1 (tagged) (one commit, published, no further work needed)
-0.0 (tagged) (one commit, published)
-0.1rc0 (untagged) (several unpublished commits)
-    0.0.1rc0 (untagged) (branch from 0.0)
-    0.0.1rc0 (tagged)
-    0.0.1 (tagged) (merged back into master as part of in-development 0.1rc0)
-0.1rc0 (tagged)
-```
+- Versions are tracked in `pretext/static/VERSION` (to be imported by both `setup.py` and the CLI
+  itself for display)
+- We use `[Major].[Minor].[BugFix]` versioning, whose history is 
+  kept in the `main` branch, with features added via pull requests.
+- Commits that aren't released on PyPI will have a `.devN` suffix.
+- When `.devN` is deemed ready for release, a single commit chainging this version to `.rcN` is made,
+  and this is built and released on PyPI. The next commit updates to `.dev(N+1)`.
+- If the `rcN` release is deemed final, a new commit removes `.dev(N+1)` and this final release is
+  released on PyPI.
+- The final commit of a particular release candidate or public release is `git tag`'d as that version
+  reflects what's on PyPI.
+- The commit following each release bumps the version to `+0.0.1` the previous version with
+  `.dev0` set.
+- Whenever deemed appropriate, the development version may be upgraded to the next Minor release instead.

pretext/static/VERSION

@@ -1,2 +1 @@
-0.5rc0
-
+0.5.0rc0