Added debug info.
Removed silly edit button from report.
Secured admin endpoints RESTful TimeSheet opertaions.
Fixed: TimeSheet page: Available Clients do not appear
(https://trello.com/c/51AAcsvn).
Added availableClients to `TimeSheetView`.
Moved availableClient/selectedClient calculation to TimeSheetView
constructor.
Moved PtoClient operations to `ClientService`.
Fixed `ContractService` `Interval` overlap calculation.