Allow disabling the resolution of the wiki based on the first part of the domain

Steps to reproduce:

• Upgrade from 15.10.11 to 16.10.11
• A wiki that has the name of the wiki:
  • test.something.domain.com (setup with nginx)
• A subwiki named "test"
• The wiki has "path based"

Results:
All the urls lead to subwiki
When I browse the main wiki, I actually ends up on the pages of the subwiki.

I cannot reproduce the problem with:
test2.something.domain.com
nor
test.otherdomain.com