switch-branch: Update links to our new documentation, Makefile polishing

I have noticed that we are using links for community documentation instead of user-docs. While at it, I did some improvements for the Makefile, because I can not leave it in that state as it was and also corrected the name of OpenWrt.

Btw: added missing "the" in superlatives.

This is compile and run tested on Turris 1.1, HBL.