Cleanups and enhancements for protobufs testing.
Cleanups and enhancements for protobufs testing.

Dynamically import protobufs classes so that the config setting
can be used to pull in the correct directory.

Each parse_* method can now optionally enforce the length of lists
and will return the parsed list for further analysis.

quattor/aquilon,guillaume-philippon/aquilon,guillaume-philippon/aquilon,stdweird/aquilon,guillaume-philippon/aquilon,stdweird/aquilon,stdweird/aquilon,quattor/aquilon,quattor/aquilon