use a queue to avoid sending commands before the connection is ready

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
make melted-node into an event emitter

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
lose callback version of sendCommand

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
rename sendCommand method

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
reset connection started flag

Signed-off-by: Tomas Neme <lacrymology@gmail.com>