client: don't disconnect from stream when paused

 * Fix stream dropping when resuming from pause. Closes #292
 * Makes streamer count accurate even while paused.
client: fix streaming not pausing and playing reliably
Revert "improve playback behavior for songs with problematic playback"

This reverts commit 09cedf7db4aa3b2f172856f40b1396037da2d230.

Reverting this commit makes #254 better but the issue is not completely
resolved.
ditch dependency on requireindex
update ytdl-core dep
don't detach encoder when paused

This prevents stream dropping when resuming from pause. It is an even
better solution for #292