MediaWiki - changing sidebar menu

Found solution here by Tom Sherman.

Gist of it is the following though (in case original page moves):
"On the off chance that you’re here because you actually want to modify your wiki’s navigation links (and not just read my complaining), I recommend that you modify the existing MediaWiki URLs and not try to create new ones. That’s what I did. Simple instructions:

1. Go to Special:Allmessages.
2. Choose a link you’ll modify. I decided I didn’t want the “Community portal” link, so that meant I would modify the:
* portal page [MediaWiki:portal] (do an in-page find on the Special:Allmessages page). Modify the existing text to change what will be rendered in the menu as the link text.
* portal-url page [MediaWiki:portal-url]. Modify the existing text to change what will be rendered in the menu as the link URL (can be internal wiki page or external URL).
3. After you’ve edited, make sure to do a full-refresh of your the page or clear your browser cache. MediaWiki is very finicky about this.

Remember, you have the choice of any of the existing links to modify. Here they are:
link text | link URL
mainpage | mainpage
portal | portal-url
currentevents | currentevents-url
recentchanges | recentchanges-url
randompage | randompage-url
help | helppage
sitesupport | sitesupport-url

Even though the pages I modified were “portal” and “portal-url,” they now have nothing to do with that topic. Those are simply the references in the database."