Update CONTRIBUTING.md

Polymer/polymer#273

Author: dfreedm

CONTRIBUTING.md

@@ -1,63 +1 @@
-# Contributing
-
-Want to contribute to Polymer? Great!
-
-We are more than happy to accept external contributions to the project in the form of [feedback](https://groups.google.com/forum/?fromgroups=#!forum/polymer-dev), [bug reports](../../issues), and pull requests.
-
-## Contributor License Agreement
-
-Before we can accept patches, there's a quick web form you need to fill out.
-
-- If you're contributing as and individual (e.g. you own the intellectual property), fill out [this form](http://code.google.com/legal/individual-cla-v1.0.html).
-- If you're contributing under a company, fill out [this form](http://code.google.com/legal/corporate-cla-v1.0.html) instead.
-
-This CLA asserts that contributions are owned by you and that we can license all work under our [license](LICENSE).
-
-Other projects require a similar agreement: jQuery, Firefox, Apache, Node, and many more.
-
-[More about CLAs](https://www.google.com/search?q=Contributor%20License%20Agreement)
-
-## Initial setup
-
-Here's an easy guide that should get you up and running:
-
-1. Fork the project on github and pull down your copy.
-   > replace the {{ username }} with your username and {{ repository }} with the repository name
-
-        git clone [email protected]:{{ username }}/{{ repository }}.git --recursive
-
-    Note the `--recursive`. This is necessary for submodules to initialize properly. If you don't do a recursive clone, you'll have to init them manually:
-
-        git submodule init
-        git submodule update
-
-2. Development happens on the `master` branch. Get yourself on it!
-
-        git checkout master
-
-That's it for the one time setup. Now you're ready to make a change.
-
-## Submitting a pull request
-
-We iterate fast! To avoid potential merge conflicts, it's a good idea to pull from the main project before making a change and submitting a pull request. The easiest way to do this is setup a remote called `upstream` and do a pull before working on a change:
-
-    git remote add upstream git://github.com/Polymer/{{ repository }}.git
-
-Then before making a change, do a pull from the upstream `master` branch:
-
-    git pull upstream master
-
-To make life easier, add a "pull upstream" alias in your `.gitconfig`:
-
-    [alias]
-      pu = !"git fetch origin -v; git fetch upstream -v; git merge upstream/master"
-
-That will pull in changes from your forked repo, the main (upstream) repo, and merge the two. Then it's just a matter of running `git pu` before a change and pushing to your repo:
-
-    git checkout master
-    git pu
-    # make change
-    git commit -a -m 'Awesome things.'
-    git push
-
-Lastly, don't forget to submit the pull request.
+See https://github.com/Polymer/polymer/blob/master/CONTRIBUTING.md