Supporting Pause/Resume, Sending Estimate logging. Corrected plot colors

PacketSender can now log Pause/Resume events into a MetricRecorder. Solved estimate error and optimal bitrate issue for test 5.7 (multiple short TCP flows).

Added Sending Estimate logging and plotting.

Fixed plotting issue on plot_dynamics.py
Now lines with the same color (in different boxes) correspond to the same flow.

Adjusting plot_dynamics.py font size according to number of variables.

R=asapersson@webrtc.org

Review URL: https://codereview.webrtc.org/1270543002 .

Cr-Commit-Position: refs/heads/master@{#9664}
8 files changed