Don't print the importance.
Move todo.txt parsing to a separate module.
Add isOverdue sub.
Rename script, mentioning importance.
Register start and due date.

The code was dead because it was skipped earlier on as soon was detected
that the $word was a key:value pair.
Add a couple of convenience functions.
The numerical priority is only relevant for importance.

Store the character value in the todo entry.
Make interface for day difference more convenient.

getDaysDiff takes a date string, getDaysLeft takes a todo item and
calculates the difference w.r.t. the due date.
Add filter for relevance.

A todo is considered relevant iff:

* It has not been completed;
* There is no start date, or the start date is today or in the past;
* Or one of the following conditions:
  * It has top priority.
  * It has priority B and is due within 30 days.
  * It has priority C or lower and is due within 14 days.
Store todos in array instead of hash.

A hash didn't make sense, and it keeps the order of the todos when
filtering.
Apply secondary and tertiary sort on due date and priority.
Only support reading from STDIN.
Adjust importance when considering working days only.

When it's Friday and a task is due on Monday, treat it as tomorrow.
Add convenience function for parsing a date in todo.txt format.
When ignoring weekends, also treat Saturday -> Monday as tomorrow.