Add exception logging on WriteLoop

[Turnerj]

Proposed Changes

Currently the socket write loop can silently fail with no ability to detect the failure. When it fails, assuming the whole socket isn't down, creates a weird situation where socket reads work fine but writes never occur.

While it would be ideal to be able to restart the write loop on such a failure, at least being able to log such a failure would be a good start.

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Further Comments

I'd assume that the vast majority of the time, the problems that affect writing to the socket also affect reading from it. The reason I'm suggesting this change is because that doesn't always seem to be the case and really, there isn't any harm adding a logging call here.