Display the user's isGlobalAdmin and isTenantAdmin properties if requested by global or tenant admin
Follow-up on review
Fix potential intermittent failures related to configuration synchronization
Code clean-up
Checking that administrator flags are return

Added 2 checks that ensure that the `isGlobalAdmin` and `isTenantAdmin`
flags return true for either a global or tenant admin on the global
admin router.
Merge branch 'issue-791-isAdmin'

* issue-791-isAdmin:
  Checking that administrator flags are return
  Follow-up on review
  Display the user's isGlobalAdmin and isTenantAdmin properties if requested by global or tenant admin
This commit introduces a new preview property for link content items.

 * `httpsAccessible`: Whether or not a link is available over HTTPS

It also fixes an issue in the embeddable check by passing in a fake
user agent.
Added a testcase that marks http-only URLs as  + some minor cleanup
#748 - minor code cleanup
Forcing users to select their account on each login
Make resource child documents registered externally
(Issue 579) Allow pluggable child documents
(Issue-579) Ensure users, groups, members and memberships are reindexed with reindexAll
(Issue 579) Message search, improve document deletes and one-many parent-child
(Issue 579) Added tests for message search
(Issue 579) Cleaning up use of constants for search document mapping names
(Issue 579) Self-review
Use API method for submitting index tasks, filter by resource type for child producer
(Issue 579) Review followup
Boost query on  field