Edit tasks

Built edit task capability + changed existing task selection to
combobox.
Part of Time-zone checking.
Removing the initial part of time-zone checking, later feature.
Made tasks reset when their time is up.
Added in validation for user input.
Removed tracking things for now.
Moved date-time into its own file.
Part 1 of moving task to its own file.
Completed moving Task to its own file.
Removed Task todo, completed in last checkin.