update MAINTAINERS.md
adding R.I. Pienaar as core-maintainer
@@ -5,6 +5,7 @@ Maintainership is on a per project basis.
### Core-maintainers
- Derek Collison <derek@nats.io> [@derekcollison](https://github.com/derekcollison)
- Ivan Kozlovic <ivan@nats.io> [@kozlovic](https://github.com/kozlovic)
+ - R.I. Pienaar <rip@devco.net> [@ripienaar](https://github.com/ripienaar)
### Maintainers
- - R.I. Pienaar <rip@devco.net> [@ripienaar](https://github.com/ripienaar)
+
