Pause currently-playing track when another is started
VLC: Undo 'isPlaying' hack

It is not needed anymore since the 'silence.wav' VLC hack.
comment++
YouTube: show channel reconnection time

It usually is very short due to re-used connections, but this may aid in
debugging.
YouTube: ignore 'unexpected EOF' errors in channel

Apparently the YouTube servers sometimes close a connection without
properly closing the HTTP stream.
YouTube: show how long it took to send a message

Usually, they are sent within a few 10s of milliseconds. But sometimes,
it takes hundreds or even more than one second (on the Raspberry Pi,
while playing audio). I suspect this is because the HTTPS connection
closed due to a timeout and a new connection had to be made.
+comment (TODO race condition)
Revert "VLC: Undo 'isPlaying' hack"

This reverts commit 117033030bf494b9e243676b401d9e006111b71c.

The hack was really needed, even after the other recent hacks,
unfortunately.
YouTube: implement restarting playback
Use standard Go functions to fetch HTTP bodies
Reorder imports
Make Channel API connection logging more useful
YouTube: Save some state; prepare for better error handling
Some extra documentation
Use the 'log' package in some places
YouTube: Improve proper HTTP handling

In particular, don't use a new bufio.Reader for each incoming message
(!). Also listen for some non-200 HTTP responses and handle those errors
more cleanly.
Rename from YouTube-receiver to Plaincast