1. The tool now displays packet loss in %.
2. It can print header information to stdout like rtp_analyze.
3. It has a command-line switch that lets you override the sample rate
guessing. With the flag "--query_sample_rate" the tool asks you to
always provide a sample rate.
4. Less decimals are printed for the estimated sample rate.
NOTRY=True
Review-Url: https://codereview.webrtc.org/2123773002
Cr-Commit-Position: refs/heads/master@{#13385}
