changed overlap check to eager failing method
Screening now uses an Interval
Timetable checks added screening for overlaps
TicketPricingStrategy now accepts a Seat and a Screening instead of a
Ticket
Adjusted visibility and convenience methods
aggregate roots now return unmodifiable views on their member collections
Screening view + presenter added
Cinema as top aggregate now returns unmodifiable views instead of
immutable copies
cinema application completed
added maven exec plugin to pom
jar artifact is executable
added documentation and extended README
added assembly for standalone .jar
updated readme with standalone jar instructions