Log scrubber now scrubs addresses even in the case where they are split
across calls to the scrubber's output io.Writer.
Added test cases to test that the writer behaves correctly across split
lines.
Added a scrubber that takes all logging output to the standard logger
and passes through a series of regular expressions to replace IP
addresses with safe strings (e.g., X.X.X.X:443).
Ensure server logs to stdout are also scrubbed
