Fix wrong int cast in expire_procs_running
Use uname -m instead of sys when looking for packages.
We define this option as 'X'. There are three places needed to be updated.

In main() function:

1. Add one item in static struct option long_options_run[] = {}
	 {"change_directory", required_argument, 0, 'X'},

2. Also add this 'X' in const char *option_string_run
	 const char *option_string_run = "aAB:cC................................X:zZ:";

3. Add the definition of option 'X' in switch statement.
	 case 'X':
	 chdir(optarg);
	 break;

And the 'X' option will work as this: makeflow -X foo Makeflow
This is the latest update of the makeflow chdir option.
To ignore the chdir in some cases, we should do the chdir after those cases.
In main function, only logfile, dag_run, and dag_clean are placed after the chdir. Their results will be written to the new directory.
The other options' outputs, such as debug.o, will be remaining at the current working directory
Remove redundant free.
Use exit/fatal.
Implemented environment variable propagation in makeflow,
batch_job, and work_queue.  Drivers for chirp, hadoop,
and mpi_queue do not support environments (yet) and will
throw an error if attempted.
Fix merge.
Cleaned up stdout messages to be a little more verbose and visually consistent.
Added environment variables to docs.
Removed comments from variable example.
No need to pass environment to wrapper generation.
Removed batch_job_submit entirely, since only batch_job_submit_simple is used at all.
batch_job_submit_simple -> batch_job_submit
Pass environment from makeflow to batch_job as a struct list of name=value.
Update docs to correspond to behavior.
Propagate environment variables to batch_job_chirp.
Added test for passing environment vars makeflow->wq.
No quotes.
Check for change_dir not null.