Performance improvement: set fmi2 values as array, not individual
FMI 2 interface exposes a way to set all variables of the same type at the same time (fmi2SetReal, fmi2SetInteger ...). Instead of calling these with an array of size 1, we should call them exactly once per communication step for all real-types, all integer-types, etc.
Same got getting variables.
Change needed in c-side of our FMIL