Chef Server 11.0.8 fixes

This PR contains fixes for:

* [CHEF-3849] redirect for login for webui ignores ssl_port
* [CHEF-3853] checksum URLs generated by POST /sandboxes do not respect 
  configured load balancer port
* [CHEF-3887] Cannot change port of erchef
* [CHEF-3889] tunable for postgresql in chef server 11 do not work when system has more than 64GB of RAM

Individual commits have detailed messages about each fix.