Enable job shell variable expansion during delocalization

[agraubert]

Right now, the remote half of delocalization (delocalize.py) accepts and expands shell variables in the context of the current job, however, matching files will not match in canine's localizer.delocalize() because the same variables are not set. We do have the information to do this, as the localizer is responsible for setting the environment variables in the first place, but we would have to be careful about using the right path contexts. This would still only allow for variables which were job inputs. Other shell variables would not expand properly.