Bug 12685: Add help file for staff search history

Bug 12685: Add help file for staff search history

This patch adds a missing help file for the staff search history page.

To test:
* Turn on EnableSearchHistory
* Do a search in the catalog
* Click your username in the top right and choose 'search history'
* Click 'help' in the top right
* Confirm that help file is there
   * note: link to manual won't work until after 2014-08-01 in the USA

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Work as described, no errors.

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>