Show encoding results, and fix a verify-encoding issue.

It turns out that Matroska files contain some bytes that are generated
at random. This PR changes the VerifyEncoding function to skip those
bytes by using the "vpxdec --md5" tool to verify that there are no changes.

In addition, a flag for showing full encoding results from list_config_results
was added.
Merge pull request #2 from google/list-with-result

Show encoding results, and fix a verify-encoding issue.