Stopped pymorse stream class from swallowing error messages

[amiller27]

Previously, when an error occurred in one of the asynchronous socket handlers represented in pymorse's Stream class, the socket was closed without printing or logging any error message, making errors in callbacks given to socket handlers impossible to debug. Now the error is sent to the logger before the socket is closed.

[adegroote]

Merged after slight rework of the commit message. Thanks for the PR.