Add confirm/feedback to hold actions

Add confirmation and feedback to hold cancel action in user's list
of hold requests.

Add feedback and notification of success/failure when placing a hold
request on a record.

Signed-off-by: Jeff Godin <jgodin@tadl.org>
Merge branch 'jeff_hold_confirmations'

Merged with manual conflict resolution on a single line in
index.html

Signed-off-by: Jeff Godin <jgodin@tadl.org>

Conflicts:
	assets/www/index.html