Add contribution page

Author: acogoluegnes

CONTRIBUTING.md

@@ -0,0 +1,36 @@
+## Overview
+
+RabbitMQ projects use pull requests to discuss, collaborate on and accept code contributions.
+Pull requests is the primary place of discussing code changes.
+
+## How to Contribute
+
+The process is fairly standard:
+
+ * Fork the repository
+ * Create a branch with a descriptive name
+ * Make your changes, run tests, commit with a [descriptive message](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html), push to your fork
+ * Submit pull requests with an explanation what has been changed and **why**
+ * Submit a filled out and signed [Contributor Agreement](https://github.com/rabbitmq/ca#how-to-submit) if needed (see below)
+ * Be patient. We will get to your pull request eventually
+
+If what you are going to work on is a substantial change, please first ask the core team
+of their opinion on [RabbitMQ mailing list](https://groups.google.com/forum/#!forum/rabbitmq-users).
+
+
+## Code of Conduct
+
+See [CODE_OF_CONDUCT.md](./CODE_OF_CONDUCT.md).
+
+
+## Contributor Agreement
+
+If you want to contribute a non-trivial change, please submit a signed copy of our
+[Contributor Agreement](https://github.com/rabbitmq/ca#how-to-submit) around the time
+you submit your pull request. This will make it much easier (in some cases, possible)
+for the RabbitMQ team at Pivotal to merge your contribution.
+
+
+## Where to Ask Questions
+
+If something isn't clear, feel free to ask on our [mailing list](https://groups.google.com/forum/#!forum/rabbitmq-users).

HTML_PERFORMANCE_TOOLS.md

@@ -344,19 +344,25 @@ $ python -m SimpleHTTPServer
 As an alternative, from the root directory of the binary distribution,
 you can launch a Java-based web server:
 
-$ bin/runjava com.rabbitmq.examples.WebServer
+```
+bin/runjava com.rabbitmq.examples.WebServer
+```
 
 The latter command starts a web server listening on port 8080, with the
 `html` directory as its base directory. You can then see the included
 sample at http://localhost:8080/examples/sample.html. To change these defaults:
 
-$ bin/runjava com.rabbitmq.examples.WebServer ./other-base-dir 9090
+```
+bin/runjava com.rabbitmq.examples.WebServer ./other-base-dir 9090
+```
 
 At last, if you want a quick preview of your results (same layout
 as the first 'consume' scenario above), ensure the scenario name is
 'benchmark' in the result file and launch the following command:
 
+```
 $ bin/runjava com.rabbitmq.examples.BenchmarkResults my-result-file.js
+```
 
 The latter command will start a web server on port 8080 and open
 a browser window to display the results.

README.md

@@ -24,7 +24,7 @@ HTML page. Learn more [here](HTML_PERFORMANCE_TOOLS.md).
 
 ## Contributing
 
-TODO
+See [CONTRIBUTING.md](./CONTRIBUTING.md) for an overview of the development process.
 
 ## Building