fix(FallFlavours): add variable path to input file
fix(FallFlavours): change listAllEvents to return all FallEvents

Previously return was a string with all FallEvents. Now it is array with
all FallEvents.
feat(FallFlavoursTester): add driver class

Driver class allows user to query new events or delete old ones.
It also shows usage for the program.
addItem method adds new element and it checks if element that is being
added already exists.
chore(FallFlavoursTester): delete unused var and change spacing