update categorical documentation

dominate value determined only though highest sum percentage by unique
item. 
Component         Percent                Slope
1                            20                          A
2                            20                          A
3                            50                          B
4                            10                          C

The dominate should be B with sum percentage value of 50.
categorical dominance calculated by sum percentage

previously dominance was determined by highest sum unique count for a
value. business logic incorrect, percentage must be used for
determination.

new implementation alters how sql results ordered. sum percentage
determines.