Produce directed acyclic graph representations of a project roadmap.
The idea is to show the steps needed to reach a goal, and the order
they need to be taken, but ignore due dates and other irrelevant
details.

# Example

~~~yaml
goal:
  label: |
    This is the end goal:
    if we reach here, there
    is nothing more to be
    done in the project
  depends:
  - finished
  - blocked

finished:
  status: finished
  label: |
    This task is finished;
    the arrow indicates what
    follows this task (unless
    it's blocked)

ready:
  status: ready
  label: |
    This task is ready 
    to be done: it is not
    blocked by anything

next:
  status: next
  label: |
    This task is chosen 
    to be done next

blocked:
  status: blocked
  label: |
    This task is blocked
    and can't be done until
    something happens
  depends:
  - ready
  - next
~~~

To run:

~~~sh
cargo run --bin roadmap2dot legend.yaml | dot -Tsvg > legend.svg
~~~

This will produce a graph like the one below.

![](legend.svg "See yaml for textual version")


# Legalese

Copyright 2019  Lars Wirzenius

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.