Updated for new formats, made into Gem with bin/rawk_log, fixed some bugs

Updated for new formats, made into Gem with bin/rawk_log, fixed some bugs

Includes renaming rawk_log to avoid conflict with an existing gem called rawk (related to awk).

Tested patch with rails 1.2, 2.3, 3.2 and log format listed for rails 4.0

Includes tests with travis-ci

Also more resilient to corrupted log entries.