Only prevent sync-continuations if explicitly enabled; otherwise it can cause near-deadlocks in the TPL-pool; avoid a dependency on the thread-pool in SocketManager

Fix: if calls Close or Dispose many times it'll throws a NullReferenceException

kill the unsent queue when connection fail; this is far more reasonable (expected), and ensures async works correctly

If the incoming socket isn't vanilla, we need to use async-read rather than socket-poll (the value of .Available is meaningless)

Fix command

TIL: Timer can randomly just *stop working* for minutes at a time; added a packemaker via the SocketManager

Prevent writer getting to the back of the Monitor queue; show EVAL example in transactions documentation