cascading open junctions

[mbouda]

If number of open junctions >1, can save on extraEquation computations by nesting them in series and using results of previously computed.
Affects:
compClrLyrEqs: 55
compLayerEqs: 43

[mbouda]

in fact, looks like may only ever need to make one extraEq... although some result in NaN coefficients... so that's unclear.