0.6.0

Change log:

• idstools-u2eve - output packet records
• idstools-rulecat: allow --local to be specified multiple times
• idstools-rulecat: --ignore option to ignore filenames
• More python 3 fixups.
• unified2 - deprecate event readers, use record readers instead
  (#14)
• u2json: --packet-hex and --printable to print raw buffers as printable
  chars and hex in addition to base64.
• u2eve: --packet-printable to include a "packet_printable" field
• u2eve: include Snort extra-data with printable data.

Commit log: 0.5.6...0.6.0