Retrieve logs > DEBUG level.

* .../logstash/log-gearman-worker.py: Only GET log lines greater than
the DEBUG log level. This will cut down the amount of processing that
logstash needs to perform and should speed up logstash log processing.
This changes the order of the $file then $file.gz GETs. Now get $file.gz
first as the log filtering on the apache side only runs on the .gz
files.

Change-Id: I8d88787ddde541f5aec2aee59c27cb1b48e5e4e5
Merge "Retrieve logs > DEBUG level."