[z-machine] Quetzal files

[Volker Blasius]

David Fillmore wrote:

> Therefore, I am proposing a standard (not obligatory, obviously)
> filename extension of .qtz for Quetzal files.

I don't like the z at the end of the filename extension - it hints
toward some kind of compression (cf. .tgz and the recurring question
"what type of compression is [z3|z5|z8]?").

Just a feeling, though; nothing tangible. But it may help to avoid
misunderstandings.

Volker