Output MAC addresses

[ctwardy]

Need MAC as a better unique ID for training classifiers.
UNSW data and bench data will have pretty reliable MACs, while IPs will change.

[ctwardy]

Branch mac_addr compiles and seems to work. ab8eceb

It reads the MACs from the first 12 bytes of the ethernet frame -- assuming they are MAC! -- and outputs them in the json as sm for source MAC and dm for destination MAC. (Follows convention of sa/da and sp/dp for IP addresses and ports.)

Example output:

/app/cisco-joy$ ./joy_static dist=1 dns=1 tls=1 bidir=0 /data/test_data/pcap/analytics.pcap > /data/test_data/out/analytics.json

{"sm":"00:0c:29:2e:cb:1c","dm":"00:0c:29:5f:97:80","sa":"192.168.12.141","da":"47.74.174.54","pr":6,"sp":54058,"dp":80,"bytes_out":0,"num_pkts_out":1,"time_start":1539281086.143142,"time_end":1539281086.143142,"packets":[],"byte_dist":...,"ip":{"out":{"ttl":63,"id":[15691]}},"expire_type":"i"}

[ctwardy]

Can @dmackenzie1 or @mkraft12 review my C changes for memory leaks? It's been a long time.
I think I'm leaving dangling pointers. Hopefully nothing worse.

[ctwardy]

This is done. Need a new ticket to add bytes_dist_per_packet which Chris Schulze's version had but is not in any of the visible forks form Cisco.