Add github contribution instructions

CONTRIBUTION.rst

@@ -0,0 +1,147 @@
+Contributing
+============
+
+Django JET is open-source and every member of the community can contribute to it. We are happy to see patches
+and improvements with Django JET. But please keep in mind that there are some guidelines you should follow.
+
+.. _requirements:
+
+Requirements
+------------
+
+* Git master branch should always be stable
+* All pull requests are made to git dev branch
+* GPL (or similar) code is not eligible for inclusion
+
+Guidelines For Reporting An Issue/Feature
+-----------------------------------------
+
+So you've found a bug or have a great idea for a feature. Here's the steps you should take
+to help get it added/fixed in Django JET:
+
+* First check if there's an existing issue/pull request for this bug/feature. Issues can be found here
+  https://github.com/geex-arts/django-jet/issues, PRs here https://github.com/geex-arts/django-jet/pulls
+* If there isn't one there, please add an issue. The ideal report includes:
+
+  * A description of the problem/suggestion
+  * How to reproduce the bug
+  * If relevant including the versions of your:
+
+        * Python interpreter
+        * Django
+        * Django JET
+        * Optionally of the other dependencies involved
+
+  * It would be great if you also make a pull request which solves your issue
+
+Guidelines For Contributing Code
+--------------------------------
+
+If you're ready to contribute back some code/docs, the process should look like:
+
+* Fork the project on GitHub into your own account
+* Clone your copy of Django JET to a separate folder
+* Install it into your demo project using ``pip install -e PATH_TO_CLONED_JET``
+* Make a new branch in git & commit your changes there
+* Push your new branch up to GitHub
+* Again, ensure there isn't already an issue or pull request out there on it. If there is and you feel you have
+  a better fix, please take note of the issue number and mention it in your pull request
+* Create a new pull request (based on your branch), including what the problem/feature is, versions of
+  your software and referencing any related issues/pull requests
+
+In order to be merged into Django JET, contributions must have the following:
+
+* A solid patch that:
+
+  * is clear
+  * works across all supported versions of Python/Django
+  * follows the existing style of the code base (mostly PEP-8)
+
+* Desirably a test case that demonstrates the previous flaw that now passes with the included patch
+* If it adds/changes a public API, it must also include documentation for those changes
+* Must be appropriately licensed (see requirements_)
+
+If your contribution lacks any of these things, they will have to be added by a core contributor before
+being merged into Django JET proper, which may take time to get to.
+
+Contribution Styles/Javascript/Translations
+-------------------------------------------
+
+Javascript/CSS/Translations need to be built each time after updating. For this you need `Node <http://nodejs.org>`_
+and `Gulp <http://gulpjs.com>`_. It's out of the scope of this tutorial to go into details, but you should
+find lots of useful references on how to install it.
+
+Node is needed for Gulp, so install it using your system package manager:
+
+.. code-block:: bash
+
+    apt-get install -nodejs
+    # or
+    yum install nodejs
+    # or
+    brew install node
+    # ...
+
+Now you are able to install Gulp globally:
+
+.. code-block:: bash
+
+    npm install --global gulp-cli
+
+Change your working directory to Django JET where ``package.json`` and ``gulpfile.js`` are located and
+install Gulp dependencies:
+
+.. code-block:: bash
+
+    npm install
+
+Now you are ready for contribution. Run Gulp from JET's directory to build all styles/scripts/locales and
+start watching for changes (gulp will rebuild files as soon they change):
+
+.. code-block:: bash
+
+    gulp
+
+Or if you want just to perform a single build without watching for changes run:
+
+.. code-block:: bash
+
+    gulp build
+
+Building produces the following files:
+
+* CSS files for each theme:
+
+  * jet/static/jet/css/themes/THEME_NAME/base.css
+  * jet/static/jet/css/themes/THEME_NAME/jquery-ui.theme.css
+  * jet/static/jet/css/themes/THEME_NAME/select2.theme.css
+
+* CSS for other JS libraries used in JET – jet/static/jet/css/vendor.css
+* Combined JS scripts of JET – jet/static/jet/js/build/bundle.min.js
+* Localization files for JS libraries:
+
+  * jet/static/jet/js/i18n/jquery-ui/
+  * jet/static/jet/js/i18n/jquery-ui-timepicker/
+  * jet/static/jet/js/i18n/select2/
+
+* Compiled Django localizations:
+
+  * jet/locale/LOCALE/LC_MESSAGES/django.mo
+  * jet/locale/LOCALE/LC_MESSAGES/djangojs.mo
+  * jet/dashboard/locale/LOCALE/LC_MESSAGES/django.mo
+  * jet/dashboard/locale/LOCALE/LC_MESSAGES/djangojs.mo
+
+You should commit generated build files together with sources.
+
+Contribution Documentation
+--------------------------
+
+If you update documentation files, you can build the html files (this is not needed with a pull-request,
+but you might wanna check how documentation will look like locally). To do so change your working directory
+to ``docs/`` inside JET and run:
+
+.. code-block:: bash
+
+    make html
+
+``docs/_build/html/`` folder will contain all html files including starting ``index.html``.