mpd 0.19.7

This is a bugfix release:
* input
 - nfs: fix crash while canceling a failing file open operation
 - nfs: fix memory leak on connection failure
 - nfs: fix reconnect after mount failure
 - nfs: implement mount timeout (60 seconds)
* storage
 - nfs: implement I/O timeout (60 seconds)
* playlist
 - embcue: fix filename suffix detection
 - don't skip non-existent songs in "listplaylist"
* decoder
 - ffmpeg: fix time stamp underflow
* fix memory allocator bug on Windows