The WIN32 CreateProcess() function does not require an .exe or .com
suffix in order to spawn an executable. Now that we have Cosmo bash
we're no longer so dependent on the cmd.exe prompt.
Now that cosmocc is unpacked into a version-specific directory under
cosmocc/, it makes more sense to put the versions in /opt/cosmocc and
maintain a symlink to the currently active one.
- Check `$COSMOCC`, defaulting to `/opt/cosmocc`.
- Try to get the full path of the repo `make.com`. I'm not aware of
a way of getting the path that defines a zsh function, so the best
fallback available is `$PWD`.
`o/$mode/*` is passed through as-is. `o/*` other than `$mode` has
`$mode` inserted. `*` has `o/$mode/` prepended.
Really leveraging zsh default tab completion here; if you have built
things with `MODE=` you can leverage that for perfect tab completion
in other modes.
