Stacktrace in case of error should possibly not include shellpy internals

[lamerman]

Here is an example

^CTraceback (most recent call last):
File "/tmp/shellpy_root/root/cr/scripts/monitor.py", line 272, in
Traceback (most recent call last):
File "/usr/bin/shellpy", line 9, in
load_entry_point('shellpy==0.4.5', 'console_scripts', 'shellpy')()
File "/usr/lib/python2.7/site-packages/shellpython/shellpy.py", line 40, in main
main()
retcode = subprocess.call(processed_file + ' ' + ' '.join(script_args), shell=True, env=new_env)
File "/usr/lib64/python2.7/subprocess.py", line 524, in call
File "/tmp/shellpy_root/root/cr/scripts/monitor.py", line 269, in main
watchgod()
File "/tmp/shellpy_root/root/cr/scripts/monitor.py", line 232, in watchgod
return Popen(_popenargs, *_kwargs).wait()
File "/usr/lib64/python2.7/subprocess.py", line 1376, in wait
sleep(30)
KeyboardInterrupt
pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
File "/usr/lib64/python2.7/subprocess.py", line 478, in _eintr_retry_call
return func(*args)
KeyboardInterrupt

Possibly it should start with the line File "/tmp/shellpy_root/root/cr/scripts/monitor.py", line 269, in main