Annual OCNS calendar using Taskjuggler

Annual OCNS calendar. This is mainly for personal use, so that I remember what organisation tasks need to be done, and when.

You need http://taskjuggler.org/ to generate the reports: On Fedora, you can run:

sudo dnf copr enable ankursinha/rubygem-taskjuggler
sudo dnf install rubygem-taskjuggler

On other machines, you can install it using gem as noted on the `RubyGems.org page<https://rubygems.org/gems/taskjuggler>`__:

gem install taskjuggler