#3 pull-logs.sh or processlogs.py can run multiple times

[Graham Ashton]

If you run pull-logs.sh and processlogs.py from a cron
job it needs to be able to detect whether or not it's
still running. If it is you end up pulling all the
files on the remote server, rather than just the ones
that were modified since pull-logs.sh.time was last
touched.