Support verbose logging

[jmurrayufo]

python-logstash/logstash/formatter.py

Line 26 in a8be251

skip_list = (

Because these are stripped down in the base class, it's somewhat problematic to re-extract them for use in debug and production. Things like lineno are particularly useful in logging. I would love to see an easier means to bypass this removal, and include them for logstash.

Would be very handy if this was just a flag passed down through the LogstashHandlers.