[Tilesathome] tah refactor - identical file names

[Matthias Julius]

Sabine Sagner-Weigl <sabine at weiglwelt.de> writes:

> I was wondering, why there are so many older request with my account
> under "Current active requests". I think I have found the cause:
>
> I am using separate upload clients. If they cannot upload for any reason
> (queue full, assumed queue full, no internet connection), the files
> to be uploaded will be overwritten by the next set of rendered request,

This is bad.  I have added the timestamp back into the zip filename as
a quick fix in the current stable branch.  I will do the same for
_unstable.

Eventually I think the filename should be something like
Z_X_Y_UUID.zip.  There is no real need for PID or hostname to be in
there.

Matthias