clarify changelog and rationalize versioning system

CHANGELOG.md

@@ -1,12 +1,15 @@
-* 2023-04-14 v1.0.1
+* 2023-04-14 v0.0.1 (was v1.0.1)
 	* The multiple colour vectors have been replaced with a single object,
 	`tax_colours`, which will cycle if there are more than 30 taxa. Having more
 	than 30 distinguishable colours is not possible anyway.
-	* Mostly under-the hood reorganization: Functions have been moved to their
-	own .R files or grouped into files with their internal helpers
+	* A bunch of under-the hood reorganization: Functions have been moved to
+	their own .R files or grouped into files with their internal helpers
 	* A test suite using `testthat` has been introduced to catch future problems
+	* rename default git branch to `main`
+	* rationalize the versioning system based on guidelines from [the r-pkgs
+	book](https://r-pkgs.org)
 
-* 2022-01-11 v1.0
+* 2022-01-11 v0.0.0 (was v1.0)
 	* **Major bug fix**
 	* this package has seen minimal changes since January of 2018 when it was
 	first written; however, in April of 2020 there was a major change in the