Add user guide link to beta icon drop down

As part of this, put the 'help' icon next to the beta icon, make the
text not greyed-out (now that it's an actual action) and provide the
link.

On hover, all three items get underlined, which is irritating, however.

Bug: 50476
Change-Id: Id65968072b7134f5864bbd96acf34fd0c23fe17c
Merge "Add user guide link to beta icon drop down"