Done and pushed to the master repository.

I made a few changes to the scripts to make them closer in style to our other
scripts and don't have a Mac to test it on, so let me know if there are still
any issues.

Sure.  I am attaching a new version of plan-ipc.  Note that this is tested only on 
the Mac, so you should verify that I haven't broken the behavior on Linux.

Robert, could you maybe make (and test) a similar change to src/downward-ipc?
This also uses "time". I guess I could adapt your change to that file easily
enough, but I don't have a Mac to test it.

This is not properly documented yet, but it's a script that can be used to run
the complete translate/preprocess/search cycle while also properly keeping track
of time for the portfolio settings we used at IPC 2008.

Usage:

$ ./plan-ipc CONFIG DOMAIN_FILE PROBLEM_FILE PLAN_FILE

where CONFIG is a configuration alias like "seq-sat-lama-2011", DOMAIN_FILE and
PROBLEM_FILE are the PDDL inputs, and PLAN_FILE is the file name for the plan
(or plans, for anytime configurations) to be generated.

Thanks! I'm currently travelling, but will have a look on Monday.

I was trying to get FD to work on Mac OS X and had trouble with the downward 
bash script.  The problem arises because the Mac's time command has a different 
API from the version on linux.

The problem can be fixed by installing "gtime" --- GNU time --- on the Mac, 
through Mac Ports and using that.

I'm attaching a new version of the downward script that checks for whether you 
are on a Mac or not, and if so, tries to use gtime.  It will print an error 
message to tell you that you need gtime, if you do.

I hope that this will be useful to you.