[p4] Same workspace for multiple user

[Robert Cowham]

> I could see where it might have been handy if perforce did 
> it's have tracking based on user at client rather than simply the client.

Perforce does track different users with different changelists in the same
client workspace - P4Win even nicely shows the pending changes in a
different colour (you can't submit another user's changelist but you can
grab their files and move them into your own).

> But I'm sure that's just asking for trouble. :)

Yup - even though possible it is generally a bad idea due to the danger of
people treading on each other's toes!