Title and Users field does not respect checkbox in IBEX

[mducle]

The Title and Users fields in the old dashboard could be hidden if the user unchecks the box Show Title and Users in Dataweb Dashboard Page.

This setting is not respected by the new WebDashboard - it always displays the Title and never displays the Users (which is always Hidden/unknown because the process variable IN:<inst>:DAE:_USERNAME seems to return null in the pvws despite it working from within IBEX (and for the JSON Bourne server).

[Tom-Willemsen]

dev notes:

• Must be done in backend
• Probably both should be always-accessible right now, but _USERNAME may be falling afoul of EPICS_CA_MAX_ARRAY_BYTES limits we put in.
• pvws pvs #74