DataChannel modifier: improved MAXScript operator

[Swordslayer]

• It would be helpful to have a separate Process-type MAXScript operator that has inputArray of floats/Point3s. At vertex level, it can be worked-around by either saving to some available vertex data channel (floats) or vertex color/map channel (point3) but if it's a game model, you have to remember to clear the data from the final model. At face level, there's no such way, and no matter the mode the MAXScript operator is in (Replace, Add, Subtract, Multiply etc) querying the face seleciton always returns empty set.
• The Script of newly added MAXScript operator in the current session is not the default script but the last script - and that one is often accessing channels that don't exist by default or custom attribute so it errors out immediately.
• While editing the script in the window that pops-up, it's continually being evaluated. I haven't finished writing a line and an error-message pops-up. I have to copy the contents, edit it elsewhere and paste it back. Doesn't have to be anything fancy, say a regular window that only updates when closed or when some update button is pressed - to keep the consistency, 'Evaluate' like in script controllers and ask to save/discard changes on dialog close.
• The theNode variable is always undefined - it can be fetched as a dependent node but since the variable is there, it'd make sense if it contained something.