Bug 18556: Clarify lost and gonenoaddress messages

Bug 18556: Clarify lost and gonenoaddress messages

This patch alters the message for the patron flasg slightly, and adds
a title to provide explicit info when hoevered

To test:
1 - Edit a patron and set gonenoaddress and lost flags
2 - Note new info in the flags section
3 - Go to 'Checkout' or 'Details' tab for patron
4 - Confirm the messages make sense
5 - Confirm you see a tool tip when hovering on messages

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>