Design Document: Resource days off should affect project scheduling

Summary

The goal is to provide a solution to issue #18 requested many times and long awaited by GanttProject users. Introduced functionality should keep core model (tasks, resources, their relations, etc) of GanttProject unchanged and work on top of it. So no new concepts for days off are expected to appear at this level. Instead, GanttProject UI should offer valuable checks and hints on project consistency regarding days off, including automatic fixes where possible, at suitable places of the UI.

User interface

Program interface

Technical details