Merge pull request #83 from tommyschnabel/Kenny

Fixed prices and removed Java 8 references
Added flight delete support to the client
Finished delete flight, started on delete reservations page
Added jQuery logic to center the navbar based on what's available
Finished reservation delete for admins
Merge pull request #84 from tommyschnabel/Tommy

Tommy
Added checks for user.admin on the client
Merge pull request #85 from tommyschnabel/Tommy

Added checks for user.admin on the client
Added flight duration to Flight object and DAO methods