Fixed or mitigated various balloon glitches (don't necessarily merge)

This is just my attempt at fixing or mitigating various balloon glitches.

Putting objects in the receptacle should work the same, regardless of whether or not you are inside the balloon.
Taking objects from the receptacle should work the same, regardless of whether or not you are inside the balloon.
"TAKE object FROM RECEPTACLE" should work as expected now. Before the game would claim that the object was an integral part of the balloon.
Opening the receptacle should print the same message, regardless of whether or not you are inside the balloon.
Use CNTFCN to prevent taking burning objects from the receptacle. It seems like the more elegant solution, if you ask me, and it means that it doesn't make any difference whether or not you are inside the balloon.
"LOOK IN RECEPTACLE" no longer says it's empty when there's something inside.

Known issues:

Using CNTFCN doesn't prevent implicit taking (e.g. "READ NEWSPAPER"). I don't think it can be handled by any action routine, so to get around it any object burned inside the receptacle automatically gets TRYTAKEBIT. No attempt is made at clearing the bit afterwards. (Doing so would probably require changing code that's currently in V-POUR-ON in zork-substrate.) Still, it seems better than the old way, which was to remove TAKEBIT and READBIT from the object.
Since the game no longer removes TAKEBIT from objects burning in the receptacle, I've probably opened up for frying them with the wizard's wand, thus removing them. Oops! And we can probably filch them, too. Double oops!

the-infocom-files / zork2