Bug 8778: Add Keyword phrase to OPAC advanced search

Bug 8778: Add Keyword phrase to OPAC advanced search

Adds a new search index to the advanced search in OPAC:
Keyword phrase
The new search option displays when the "More options" are
selected.

To test:
- Apply patch
- Go to Advanced search in OPAC
- Look at the search pull downs
- Verify everything looks correct
- Click "More options"
- Verify the Keyword phrase search option shows
- Test if it works correctly

Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>