Add a CONTRIBUTING.md file, to appear on new Issue/PR pages

[longjon]

I've just realized that if you create a file called CONTRIBUTING.md, a link to it will appear on the GitHub new Issue and new PR pages (https://github.com/blog/1184-contributing-guidelines).

This seems like a good opportunity to provide some up-front tips on making contributions, and hopefully to improve the S/N on Issues.

I've drafted such a file here. Additions and suggestions are welcome (or can come in future PRs), but let's try to keep it succinct and to-the-point and with an obvious organization so that it gets read.

This should replace the bug reporting guide I created on the wiki (https://github.com/BVLC/caffe/wiki/Reporting-Bugs-and-Other-Issues), and probably also the recently added Contributing page by @BlGene (https://github.com/BVLC/caffe/wiki/Contributing), but it links to the more detailed contributing guide at http://caffe.berkeleyvision.org/development.html (which could stand a bit of reorganization).

[lukeyeager]

hopefully improve the S/N on Issues

👍

[ronghanghu]

LGTM

[BlGene]

👍 There do seem to be a lot of usage questions in issues.

[BlGene]

A Stackexchange (Area51) QA system might be a better long term solution if people are willing to give it a try.

The Area51 caffe QA website requires followers and questions with up votes, in order to migrate through the stages of: defined -> committed -> beta so any contribution is appreciated. As usual with these sites all control is based on reputation points earned.

@longjon @shelhamer @jeffdonahue @everyone
This would probably first require a mailinglist vs QA debate but if support can be found for this the CONTRIBUTING.md file might be a good place to put a link.

[bhack]

http://answers.opencv.org/questions/

[BlGene]

@bhack
Yes, they got their own shiny custom site because they have enough users. In case you were suggesting it, having caffe questions on the opencv QA would not be a nice solution.

[seanbell]

👍

[longjon]

Okay, I'm going to go ahead and merge this pure-documentation update. Edits are welcome as PRs.

We've discussed setting up a QA style site (like OpenCV's or StackExchange) before, but probably don't have the bandwidth to manage that. If someone from the community wants to set that up, I think we'd be happy to link to/endorse it, and provide a (sub)domain name. Otherwise an actual StackExchange or the Caffe tag on StackOverflow are fine options as long as that fits with how StackExchange works, I don't really know.