"prereq_no_process" feature

Searches the `ps` list for anything that looks like the daemon that might
already be running.

Both the program name and arguments are checked, as it appears different
operating systems vary as to how they populate `ps`:  On ubuntu, my daemon
looks like:

    /path/to/perl /path/to/program args

but on CentOS, the very same code shows up as:

    /path/to/program args
Merge pull request #43 from karenetheridge/topic/detect_dupe_process

"check_duplicate_process" feature