Extended DayType and implemented DayTypeParser
Handling commas in day types (ex 'Pt/Sob.,Sob./Św.') & Nightly day type points to just one day of week (ex just Pt instead of Pt and Sob for 'Pt/Sob')
Implemented toString(), equals(), hashCode() and additional constructors for DayType class
Replaced old DayTypes enum with new DayType class
DayTypeParser sets nightly value on DayType based on passed parameter instead of default ones
Extended DayType.match() to handle nightly schedules and daily schedules with after-midnight departures