Dynamic number of slots and program changes in Performance Mode

A variable number of slots in Performance mode. A system parameter that lets you define the number of slots you have in a performance (which of course, depends on the foot controller you use: one with 3 programs per bank, one with 4 programs per bank, ...).
Generating the right midi program change depending on this value (if for example 3 programs per bank: performance 1 slot 1 = pgm chg 1, performance 1 slot 2 = pgm chg 2, performance 1 slot 3 = pgm chg 3, performance 2 slot 1 = pgm chg 4, ...)