Add documentation for including breakpoints in a RHS

[Schlevidon]

Summary

Breakpoints placed in a RHS will not trigger when solving with IFDIFF because the RHS is exported into a new file, which does not contain the breakpoints from the original RHS.

An easy fix would be to use the keyboard command instead, which will be transferred over to the RHS and any derived functions. We should document this for users.

Example

RHS

function dy = rhsBreakpoint(t, y, p)
dy = 1;
keyboard;
x = 5;
if y > x
    dy = 0;
end
end

which will be preprocessed as

function dy = rhs_preprocessed_rhsBreakpoint(datahandle,t,y,p)
    dy = 1;
    keyboard;
    x = 5;
    switchEval_if_1 = x - (y);
    conditionValue = ctrlif( switchEval_if_1, false, true, 1, 0, datahandle );
    if conditionValue
        dy = 0;
    end
end

Note that the keyboard command is also present in the switching function

%rhs_preprocessed_rhsBreakpoint:1/1/0
function switchingValue = sw_rhs_preprocessed_rhsBreakpoint_C717E8E3_1_1(datahandle,t,y,p)
    keyboard;
    x = 5;
    switchEval_if_1 = x - (y);
    switchingValue = switchEval_if_1;
end