misc: updated shabang for python script

The default python on MacOS doesn’t have an alias to python2.
The official python version supported in gem5 is Python2.7.

This patch updates the shabang according to the version required in gem5.

Change-Id: I9533c0f7858b5b3cab0ef101be1ee5cd718105b0
Reviewed-on: https://gem5-review.googlesource.com/c/15375
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

misc: Update #!env calls for python to explicit version

In some newer Linux distributions, env python default to Python 3.0. This
patch explicitly uses "python2" instead of just "python" for all scripts
that use #!

Reported-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>

Merge zizzer:/bk/m5
into zeep.eecs.umich.edu:/z/saidi/work/m5

add a few more options to the help menu

Simple updates to pbs and send.py

util/pbs/pbs.py:
Change the default so that we do not get mail under any circumstances
from pbs.
util/pbs/send.py:
Add a -n flag to send.py that causes the Base directory to *not*
sync with the Link directory

Better pool job handling

util/pbs/job.py:
the default jobfile is now Test.py in the root of the jobs directory
util/pbs/pbs.py:
Clean up the qsub options handling and add job dependencies
util/pbs/send.py:
the default jobfile is now Test.py in the root of the jobs directory
add a flag to depend on your checkpoint
add a flag to specify your node type
create the base directory if it doesn't exist

don't write the pbs jobid here, do it in send.py so we know
what it is sooner
Don't handle sigstop since you're not allowed to.

util/pbs/send.py:
write the pbs jobid here in send.py so we know what it is sooner

Totally re-work the way that jobfiles are done so there is more
information that can be used for other aspects of sending jobs.
New graphing output stuff with matplotlib.

util/pbs/job.py:
Shuffle code around and create the JobDir class which encapsulates
all of the functionality needed for making, organizing, and cleaning
a job directory.
Better status output
util/pbs/jobfile.py:
Majory re-working of the jobfile code.
A job file now consists of several objects that describe how
jobs should be run, it includes information about checkpoints,
and graphing.
util/pbs/send.py:
use the new jobfile code.
deal with the 15 character limit of pbs by truncating the name and
using the raj hack.
util/stats/db.py:
fix the __str__ function for nodes
provide __getitem__ for the Database class
util/stats/stats.py:
use the jobfile stuff to figure out what the proper naming
and organziation of the graphs should be.
move all output code to output.py, get rid of ploticus and use
matplotlib

Updates to job scripts to accept more than 15 characters of jobname
Make the Link directory even more useful by working with
sub-directories.

util/pbs/job.py:
Expose JOBNAME as a separate parameter from PBS_JOBNAME. If the
former exists, it is used as the jobname for starting the job, if
it doesn't exist, PBS_JOBNAME is used. This is to get around the 15
character maximum pbs job name length. While we're at it, shuffle
things around to hopefully make things a bit more clear.
util/pbs/send.py:
Make the Link directory functionality more sophisticated, copy
sub-directories and links to directories. (we still don't copy
dotfiles though)
Add the setname() function to contact pbs and use raj's hack to
tell the webpage about longer jobnames. (it's gross, don't look)
truncate the pbs job name to 15 characters so that it works.

Improvements to send.py to allow the user to specify the jobfile

util/pbs/send.py:
Allow the user to specify the jobfile

Make it so we append jobs to the joblist in the for loop not
outside of the loop so we get all of the jobs, not just the
last one.

util/pbs/send.py:
fix indent

More fixes to the pbs stuff to make it more robust.

sim/pyconfig/SConscript:
Embed the jobfile.py script into the binary so that we don't
need to copy it into the Base directory every time.
test/genini.py:
Add the util/pbs directory to the path so we can get to
jobfile.py
Add a -I argument to set to add to the path.
util/pbs/pbs.py:
Create a MyPOpen class. This is a lot like the popen2.Popen3 class
in the python library except that my version allows redirection of
standard in and standard out to a file instead of a pipe.
Use this popen class to execute qsub or ssh qsub. This was important
for the ssh version of qsub because we need to pipe the script into
standard in of ssh so that the script can get to the qsub command.
(Otherwise we have a problem discovering the path.)
util/pbs/send.py:
Tweak the script so it figures out paths in NFS correctly.
Use the new system for running qsub.

More fixes for running from anywhere.

util/pbs/send.py:
always access the job directory via full path

Fixes to thes pbs send script

util/pbs/send.py:
- add a -d to set the job root directory allowing one to run
send.py from anywhere.
- specify full paths to files instead of relative paths to make -d
work and to allow ssh qsub to work again.
- make the Link directory only copy links that point to regular files.

Make pbs submission scripts available to all.
Fix up configuration scrupts to have better support for
running on the simulation pool.