added transferTicketOwnership, refundTicket and searchEvents

[Muhindo-Galien]

This PR introduces three additional advanced functions to enhance this canister'sfunctionality.

Transfer Ticket Ownership

The transferTicketOwnership function allows users to transfer ownership of a ticket from one user to another. It takes the following parameters:

• ticketId: The ID of the ticket to be transferred.
• currentHolderId: The ID of the current ticket holder.
• newHolderId: The ID of the new ticket holder.
• password: The password of the current ticket holder for authentication.

Example usage:

transferTicketOwnership({
  ticketId: 'abc123',
  currentHolderId: 'user1',
  newHolderId: 'user2',
  password: 'password123',
});

Refund Ticket

The refundTicket function allows ticket holders to request a refund for their ticket. It takes the following parameters:

• ticketId: The ID of the ticket to be refunded.
• password: The password of the ticket holder for authentication.
  Example usage:

refundTicket({
  ticketId: 'abc123',
  password: 'password123',
});

Event Search

The searchEvents function enables users to search for events based on various criteria. It takes the following parameters (all optional):

• eventName: The name of the event.
• organizer: The organizer of the event.
• date: The date of the event.
• location: The location of the event.

Example usage:

searchEvents({
  eventName: 'concert',
  organizer: 'John Doe',
  date: '2023-08-15',
  location: 'New York',
});

Please refer to the function descriptions and examples above for a high-level understanding of their usage within the Ticket Management System.

[dev-opus]

The searchEvents function would break the code. an event does not have date and location fields. Please remove those fields.