usage.txt

List events:
node app.js list-events

List clients:
node app.js list-clients

Add event:
node app.js add-event <event_name> [<age_restriction (18+)>]
node app.js add-event SomeEvent 
node app.js add-event SomeEvent 18+

Remove event:
node app.js [remove-event, delete-event] <id>

Edit event:
node app.js edit-event <event_id> <property_to_edit> <value> ...
node app.js edit-event 1 name FirstEvent
node app.js edit-event 1 ageRestriction 18+
node app.js edit event 1 name Kupon ageRestriction 18+

Add client:
node app.js add-client <client_name> <sex м/ж> <age>
node app.js add-client Пешо м 24

Add client to event:
node app.js add-client-event <client_name> <event_id>
node app.js add-client-event Пешо 1

List clients in event:
node app.js list-event-clients <event_id>
node app.js list-event-clients 1

Remove client from event:
node app.js remove-event-client <event_id> <client_name>
node app.js remove-event-client 1 Пешо