Clarified docs for floor(), ceiling() and round().
Clarified docs for floor(), ceiling() and round().

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