[metapost] improving MetaPost documentation (was: [mp-implementors] [mpman] appendix A: withcolor and withprescript/withpostscript)

[Karl Berry]

    Do we want our "showcase" to be in the manual, or do we want it to
    be in another document?  My guess is that we want it to be in
    another document

Yes, separate document.

     consider using a wiki (or similar) for the showcase.  

If you or anyone would like to set up a MetaPost wiki and start
populating it, it sounds good to me.  (For a variety of reasons, it
wouldn't be a quick process to create one on tug.org.)

    If we do this, then we might want the wiki to be
    "officially" part of MetaPost (just as the manual is)

A wiki would obviously be entirely separate from the metapost
distribution, so I'm not sure what this would mean.  But also I don't
see that it's necessary to figure out such details before it even
exists.  Just start the wiki and see how it develops :).

Best,
k