Could Not Dispatch 0.7.2

• The card uses much less CPU and memory (issue #4). A still picture was read, decoded and
  scaled at the card's full frame rate, and ffmpeg sized its threads on every core it could
  see, which in a container limited to one CPU are all the host's. A picture now enters at
  5 fps, while the stream still leaves at the frame rate you set, and the threads are fixed.
  Limited to 1 CPU, a 1080p picture went from 0.73 to 0.37 core and from 910 to 291 MB, a 720p
  picture from 0.55 to 0.18 core and from 558 to 183 MB, and an 8-second 1080p video from 901 to
  287 MB with almost the same CPU. The first megabyte of a 1080p picture arrives in 1.30 s
  rather than 4.50 s. The card with the channels in use gets the same saving, and its text is
  read five times a second instead of on every frame.

Commits

• 445e027 Release 0.7.2
• b053fcd docs: what the card costs, and why a picture enters at 5 fps
• b1b9c99 A picture enters at 5 fps and the encoder's threads are fixed