More exception handling in stream
More exception handling in stream

Handle IOError that can occur when reading from the stream,
and ValueError that can be raised by the JSON parser.

Change-Id: Ic9dc60e048f0f747daf8b34c7b6d8d90c11bb1e0

dpursehouse/pygerrit2,dpursehouse/pygerrit,morucci/pygerrit,benjiii/pygerrit,sonyxperiadev/pygerrit,gferon/pygerrit2,markon/pygerrit2