Bug 20421: Inform staff that patron does have the title checked out during placing...

Bug 20421: Inform staff that patron does have the title checked out during placing hold

Test plan:
1) Enable the CheckPrevCheckout and DisplayMultiPlaceHold system preferences
2) Have a patron with some checkouts history
3) Try to place hold on one of titles from history for this patron
4) You should see an information at the top of confirm request page, but
you still should be able to place a hold
5) Try this with multiple titles - one or more of them should be from
history
6) You should see this information in "Information" column
7) There is also new column placed at the beggining with checkbox, you
could uncheck it for titles you do not want to place a hold on it
8) Confirm the hold is placed only on checked titles

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Bin Wen <bin.wen@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>