Tracking info regex for USPS should detect 1 or 2 digit day of month
Refactors changes made for extracting event information

Cleans things up a bit and uses a struct to give a more objecty feel
Merge pull request #134 from Shopify/refactor/tracking_info_regex_for_usps_detects_1_or_2_day_dom

Refactor/tracking info regex for usps detects 1 or 2 day dom