Auto merge of #6313 - bundler:rubymorillo-patch-2, r=colby-swandale

Update Bundler Contributor Guidelines README

Thanks so much for the contribution!
To make reviewing this PR a bit easier, please fill out answers to the following questions.

### What was the end-user problem that led to this PR?

The problem was...
...the contributor guide was is too long and too confusing. It was difficult to determine what information needed to be reviewed in what sequence. We wanted to make the guidelines easy to read and easy to follow.

### What was your diagnosis of the problem?

My diagnosis was...
...to condense the information
### What is your fix for the problem, implemented in this PR?

My fix...
to condense the information presented and truncate the number of sections. See changes:

![Before](https://user-images.githubusercontent.com/3386562/36821134-7c261d02-1cbf-11e8-9114-ea301da9d91f.png)
![After](https://user-images.githubusercontent.com/3386562/36821143-87472528-1cbf-11e8-884b-5c1334322d56.png)

### Why did you choose this fix out of the possible options?

I chose this fix because...
...it's a quick win!

1 files changed, 17 insertions, 27 deletions

diff --git a/doc/contributing/README.md b/doc/contributing/README.md
index 55c742d2ae..363864026a 100644
--- a/doc/contributing/README.md
+++ b/doc/contributing/README.md
@@ -1,38 +1,28 @@
-# Contributing to Bundler
+# Bundler Contributor Guidelines
 
-Welcome to Bundler! We are so happy that you're here. We know joining a new open source project can be daunting, so here's a quick overview of what you can expect from this documentation.
+Thank you for your interest in making Bundler better! We welcome contributions from everyone. Dozens of contributors like you have submitted feature improvements, fixed bugs, and written new documentation. [Join the Bundler Slack community](http://slack.bundler.io/) to connect with the Bundler core team and other contributors like you.
 
-*Something missing?* Send us a [pull request](../development/PULL_REQUESTS.md)!
+Before submitting a contribution, read through the following guidelines:
 
-**Recommended first steps**
+* [Bundler Code of Conduct](https://github.com/bundler/bundler/blob/master/CODE_OF_CONDUCT.md) (By participating in Bundler, you agree to abide by the terms laid out in the CoC.)
+* [Issue Reporting Guidelines](https://github.com/bundler/bundler/blob/master/doc/contributing/ISSUES.md)
+* [Pull Request Guidelines](https://github.com/bundler/bundler/blob/master/doc/development/PULL_REQUESTS.md)
 
-- Join us in the Bundler slack! Generate an invite [here](http://slack.bundler.io/)
-- *If you're interested in helping with code:*
-  - Get a quick overview of our [development process](../development/README.md)
-  - [Setup your machine for development](../development/SETUP.md)
-  - Checkout [How you can help: your first contributions!](HOW_YOU_CAN_HELP.md) for a list of suggestions to get started
-- *If you're interested in helping with documentation:*
-  - Read up on [how documentation works for Bundler](../documentation/README.md)
-  - Learn about our [documentation vision](../documentation/VISION.md)
+And be sure to set up your development environment:
 
-You can start learning about Bundler by reading [the documentation](http://bundler.io). If you want, you can also read a (lengthy) explanation of [why Bundler exists and what it does](http://bundler.io/rationale.html).
+Once you've reviewed the above guidelines, be sure to [set up your development environment](https://github.com/bundler/bundler/blob/master/doc/development/SETUP.md).
 
-## [How you can help: your first contributions!](HOW_YOU_CAN_HELP.md)
+## Contributing to Bundler
 
-A detailed overview of how to get started contributing to Bundler, including a long list of suggestions for your first project.
+Here are the different ways you can start contributing to the Bundler project:
 
-## [Bug triage](BUG_TRIAGE.md)
+* [First contribution suggestions](https://github.com/bundler/bundler/blob/master/doc/contributing/HOW_YOU_CAN_HELP.md)
+* [Adding new features](https://github.com/bundler/bundler/blob/master/doc/development/NEW_FEATURES.md)
+* [Triaging bugs](https://github.com/bundler/bundler/blob/master/doc/contributing/BUG_TRIAGE.md)
+* [Writing documentation](https://github.com/bundler/bundler/blob/master/doc/documentation/WRITING.md)
+* [Community engagement](https://github.com/bundler/bundler/blob/master/doc/contributing/COMMUNITY.md)
 
-Want to take a stab at processing issues? Start here.
 
-## [Getting help](GETTING_HELP.md)
+## Supporting Bundler
 
-How to get in touch with folks who can help when you're stuck. Don't worry! This happens to all of us. We're really nice, we promise.
-
-## [Filing issues](ISSUES.md)
-
-We see a lot of issues in the Bundler repo! Use this guide to file informative, actionable issues.
-
-## [Community](COMMUNITY.md)
-
-Learn more about our goals for the Bundler community and the ways you can help us build better together.
+[Ruby Together](https://rubytogether.org/) pays some Bundler maintainers for their work, funded directly by the Ruby community. If you’d like to support Bundler with a financial contribution, [become an individual sponsor](https://rubytogether.org/developers#plans). We also welcome financial [contributions from companies](https://rubytogether.org/companies#plans), too! (You can also support us through [Open Collective](https://opencollective.com/rubytogether).)