Adding mongoproto.OpDelete and mongoproto.OpUpdate to cmd/pcap_converter

[timvaillancourt]

Adding mongoproto.OpDelete and mongoproto.OpUpdate to 'pcap_converter' now that they're supported in tmc/mongoproto after this PR was merged: tmc/mongoproto#2.

This resolves 2 of 3 missing ops in #40, so I will close #40 if this is merged and open a getmore-specific issue for the final missing op.

Example update op:

$ bsondump flashback.bson 2>/dev/null | grep \"op\":\"update\" | head -1
{"ns":"test.lag_check","ts":{"$date":"2016-10-14T19:02:19.400Z"},"op":"update","query":{"_id":1},"updateobj":{"_id":1,"x":1}}

Example delete (remove) op:

$ bsondump flashback.bson 2>/dev/null | grep \"op\":\"remove\" | head -1
{"ns":"test.items","ts":{"$date":"2016-10-14T19:03:38.380Z"},"op":"remove","query":{"_id":{"$oid":"58012bb839f7e32dab46b8ae"}}}

Any thoughts/suggestions appreciated!

[tredman]

Thanks!