video_recorder skips frames even when they arrive just a fraction too early

[cbteeple]

Package

image_view

Feature

video_recorder skips frames when they arrive too soon to ensure proper framerate

Expected Behavior

If a camera stream is running at 30 fps, then video_recorder should be able to save a 30fps video without dropping frames

Actual Behavior

video_recorder skips frames when they arrive even a fraction of time too early. Since the opencv VideoWriter class expects frames to be given at the set framerate, we end up with a shorter video that plays back faster.

[mikeferguson]

Calling this a duplicate of #274 - at some point sec_per_frame needs a refactor