Bug 20467: Add ability to batch add items to a course

Bug 20467: Add ability to batch add items to a course

Some librarians have requested the ability to batch add items to a
course using the same settings for all items.

Test Plan:
1) Apply this patch
2) Create a new course
3) Click the new 'Batch add reserves' button
4) Enter some valid and invalid barcodes in the text box, add some settings
5) Submit the batch, note the results list added items and invalid barcodes
6) Note the valid items were added to the course

Signed-off-by: Séverine QUEUNE <severine.queune@bulac.fr>
Signed-off-by: Maksim Sen <maksim.sen@inlibro.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>