[RFC] adding zmktemp command

[Clinton Bunch <cdb_zsh@xxxxxxxxxxx>]

I'm thinking of adding a zmktemp command either in a new module (e.g. 
zsh/tempfile) or in the zsh/files module.

My rationale is that mktemp is really useful for creating temporary 
files but is not available by default on all systems and on some on 
which it is available its options and function can diverge wildly (HP-UX 
is an especially egregious example). Building it into the shell would 
give a consistent interface for zsh scripts to create temporary files.

The advantage I can see to being it's own module, is it could be 
backported and separately packed for Long-Term Supported OS. (Mostly 
thinking of Enterprise Linux distributions)

But it also seems like it would be a good fit into the zsh/files module 
(mktemp and zf_mktemp instead of zmktemp)

Thoughts?