Staging tree on Github

[Jo-Philipp Wich]

Hi all,

there's some extremely popular demand to be able to contribute through
Github and a while back we already decided to utilize staging trees in
order to consolidate commits being made to master.

Due to this I decided to open a staging tree on Github which you can do
your PRs against.

The plan for the tree is the following:

- PRs will be merged and staged here
- Accumulated changes are regularly transferred to master and the tree
  is subsequently getting rebased

The main reason for using this approach is to avoid merge commits
cluttering the main history plus the ability to handle both the Github
oriented PR workflow as well as the mailing list oriented patchwork one.

Regards,
Jo