Finish packet counting, problem 1c
Finish packet counting, problem 1c

This could really use with a header file though.  Maybe that'll come later.

--- deliverables ---
1c: Sniff packets on an interface for a user-specified amount of time.  The
user-specified duration should be accepted as a command line argument.  For
every packet captured, a counter should be incremented and shown as output on
the screen.

sjbarag/ECE-C433,sjbarag/ECE-C433,sjbarag/ECE-C433