website: override automatic linking of list items for softlayer dc
website: override automatic linking of list items for softlayer dc

This avoids a conflict with #datacenter later on the page. We're mixing
histroic manually specified anchors with generated anchors (via
redcarpet / middleman-hashicorp) so we have to manually override the
automatic generation here.

I was tempted to rewrite the old manual anchors to use the automatic
generation, but there is no way to maintain backwards compatibility,
so will leave that for a time when it is appropriate for us to break
links (or redirect them, etc).

Fixes #3916

42wim/consul,youhong316/consul,calgaryscientific/consul,42wim/consul,vamage/consul,calgaryscientific/consul,vamage/consul,scalp42/consul,hashicorp/consul,kingland/consul,youhong316/consul,kingland/consul,hashicorp/consul,vamage/consul,calgaryscientific/consul,42wim/consul,vamage/consul,youhong316/consul,scalp42/consul,hashicorp/consul,vamage/consul,youhong316/consul,42wim/consul,scalp42/consul,hashicorp/consul,scalp42/consul,kingland/consul,youhong316/consul,calgaryscientific/consul,scalp42/consul,calgaryscientific/consul,kingland/consul,kingland/consul,42wim/consul