Undo Travis CI diagnostics

A number of diagnostic commands were added to the .travis.yml config
file, to help diagnose a testdata load issue. That issue has no been
resolved, so this commit removed those no-longer-necessary diagnostic
commands.
Merge branch 'master' of github.com:pcolby/bipolar
Improve readability
Correct default wire-type 5 size

32-bits = 4 bytes, not 8.
Don't treat length-delimited data of unknown type as packed.

They often aren't packed, and it isn't same to assume they are. Instead
treat such unknown data raw binary strings (aka "bytes").
Rename length-delimited field parsing functions.

The original names being a left-over from my own personal
prefixed-length strings. Length-delimited is the Google Protocol
Buffers terminology.
Support protobuf group fields

Although they are deprecated, this change allows "start group" and "end
group" fields to work.
Use tags, not tagPath's for embedded messages.

The latter works fine too, but the former is adequate, neater, and
closer to what the original *.protoc files would look like (as well as
the protoc --decode_raw output).
Log parse failure cases.