scripts: fix benchmark parsing for wire_protocol-test
scripts: fix benchmark parsing for wire_protocol-test

This fixes the existing parsing for row-wise conversion, and adds
parsing for the new columnar conversion, writing the columnar stats as a
new workload "WireProtocolBenchmark_columnar" and plotting results as
"wire-protocol-test_columnar".

Change-Id: I9d1ac45cf730674a4aa3b7d1f7f60b6919e3eeb1
Reviewed-on: http://gerrit.cloudera.org:8080/15651
Tested-by: Kudu Jenkins
Reviewed-by: Grant Henke <4cf7ebbe638391c4d27a10cf751b99bdbd1a1880@apache.org>

helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu,helifu/kudu