Ignore $wgMobileUrlTemplate when host is an IP address

If host is given as an IP address, do not update it based
on the rules set in $wgMobileUrlTemplate

This patch is mostly needed for debuging: when used from
Vagrant, navigating to 127.0.0.1:8080 rewrites it as
127.m.0.0.0:8080, which obviously does not work.

Having $wgMobileUrlTemplate set to the same value as in
production allows Zero team to see if the post-parse
DOM rewrite handles Zero links correctly under various
settings.

Change-Id: I33fc78637494825f15dd46885c4b82676c723925
Merge "Ignore $wgMobileUrlTemplate when host is an IP address"