chore: update contributing guidelines

Author: Steven

CONTRIBUTING.md

@@ -1,15 +1,5 @@
 ## Contributing
 
-Development happens on the `master` branch. When a release is
-being prepared, it is tagged on that branch with a `vX.0.0-rc#`
-tag, and released to npm with the `next` tag. Typically,
-releases that start from the `master` branch will increase
-the major version number.
-After release, changes are continued on a `X-rel` branch.
-On that branch, bugfixes will increase the patch number, while
-backported features (that don't break the interface) will
-increase the minor version number.
-
 Please use the github issue tracker for any bugs or feature requests,
 email sent to the maintainer(s) will probably be ignored.
 If you would like to backport a feature from master to a release
@@ -19,10 +9,10 @@ If you would like to contribute bug fixes or new components,
 make sure there is an existing issue for it, and make a pull
 request referencing the issue.
 
-If your changes cause problems with how the library was used
-before, please write `[breaking]` att the beginning of the commit
-title (and pull request if applicable), and describe what has
-changed in the commit message.
+We use [conventional commits](https://www.conventionalcommits.org) to write commit messages.
+If your changes cause problems with how the library was used before,
+don't forget to write `BREAKING CHANGE:` inside the commit message body,
+followed by a description of what has changed and how to adapt for it.
 
 Most components have unit tests, and basic proper behaviour is always
 tested, but we don't have full coverage (yet) of all the component code.