[AstroPy] Version Control for AstroPy

[Thomas Robitaille]

Hi everyone,

At the end of last week we asked whether you would approve of using
the git version control system with hosting on GitHub for the core
AstroPy package, and the final results are 49 in favor (74%) and 17
against (26%).

Given that a strong majority is in favor of the proposition, that the
poll numbers imply that a majority of people have voted, and that it
is unlikely that any version control system would get unanimous
approval, we have decided to go with the results of the poll and
recommend that we use git with GitHub.

However, we don’t want to ignore those of you who voted against, and
we want to address the concerns raised on the list, including from
people who voted negatively in the poll. Therefore, we want to clarify
the following points:

- Future polls will be preceded by at least a few days of discussion
before being created, and polls will be more nuance than simply
“yes”/”no” (allowing, for example, “don’t care,” “don’t know,” or
“abstain/protest”).

- Clear instructions and assistance will be provided so that anyone
not familiar with git and/or github will have no problems
contributing, and that no one will be left out. Instructions will also
be provided for how svn and hg can be used to talk to git
repositories.

- With your help, we will write a clear document outlining a strict
workflow for contributing to the core package via git. This will
likely be based on the gitwash/numpy/scipy guidelines.

- Importantly, affiliated packages are under no obligation to use
git/github until they are merged with the core package. Even once they
are merged with the core package, future development on the component
can still technically be done with hg or svn, so long as the changes
are ultimately submitted via git.

We hope these points will be acceptable to people who voiced concerns
on these topics, and that we still have you all on board. If not,
please let us know how we can address your concerns. We also welcome
other feedback on any of these points.

We are really excited that things are moving forward, where previous
discussions in the past have failed, and the core astronomy library
now seems a tangible goal more than ever!

Cheers,

Thomas, Erik, and Perry