Removed shift/reduce conflict in the xpath parser.
Removed shift/reduce conflict in the xpath parser.

YorickPeterse/oga,jeffreybaird/oga,ttasanen/oga,YorickPeterse/oga,dfockler/oga,ttasanen/oga,YorickPeterse/oga,dfockler/oga,dfockler/oga,ttasanen/oga,jeffreybaird/oga,ttasanen/oga,jeffreybaird/oga,dfockler/oga,jeffreybaird/oga,YorickPeterse/oga,altmetric/oga,YorickPeterse/oga,dfockler/oga,altmetric/oga,altmetric/oga,altmetric/oga,jeffreybaird/oga,ttasanen/oga,altmetric/oga