Broken links in docs

[DomGarguilo]

There are some broken links in the docs that need updating/fixing. I briefly looked through some of the pages and there are probably others but here are a few that I found:

• The log4j links probably need to be updated to lo4j2 in this section: https://accumulo.apache.org/docs/2.x/administration/in-depth-install#configuration
• Looks like the manager and tserver link needs to be corrected in this sections: https://accumulo.apache.org/docs/2.x/administration/in-depth-install#cluster-specification
• The Zookeeper acls link in this section: https://accumulo.apache.org/docs/2.x/administration/upgrading#upgrading-from-110-or-20-to-21

[AlbertWhitlock]

Dom.....I can take this one.

[rsingh433]

I will take on this one.