Bug 15377: Allow removal of 'checked out' items from course reserves

Bug 15377: Allow removal of 'checked out' items from course reserves

1) removes the restriction of not allowing a reserve to be removed if it is onloan
2) adds a column to the display that says with the item is checked out or available based on the onloan flag

testplan: add an item to course reserves, check the item out, check that the Ciruclation column changes to Checked Out and that you can remove it

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Hannah Olsen <holsen@duncanville.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>