Update sdk tutorials repo CONTRIBUTING.md (#732)

* Update CONTRIBUTING.md

iterative improvements for our contributing, taking lessons learned from the Pylons docs kickoff https://docs.google.com/document/d/1YqyF4CVx_wEN-MPdXtW7krkhhDWdSfb8LMrSeFBZFtw/edit?usp=sharing

* Update CONTRIBUTING.md

Author: Barrie Byron

CONTRIBUTING.md

@@ -14,6 +14,26 @@ Thank you for helping us to create and maintain awesome tutorials.
 - To provide feedback, file an issue and provide abundant details to help us understand how we can make it better.
 - To provide feedback and a fix, you can make a direct contribution. This repo is protected since we provide the code and the docs to help you learn. If you're not a member or maintainer, fork the repo and then submit a PR from your forked repo to master.
 
+## Writing and contributing 
+
+We welcome contributions to the tutorials. Our technical content follows the Google developer documentation style guide:
+
+- [Google developer documentation style guide](https://developers.google.com/style)
+- [Highlights](https://developers.google.com/style/highlights)
+- [Word list](https://developers.google.com/style/word-list)
+- [Style and tone](https://developers.google.com/style/tone)
+- [Writing for a global audience](https://developers.google.com/style/translation)
+- [Cross-references](https://developers.google.com/style/cross-references)
+- [Present tense](https://developers.google.com/style/tense)
+
+The Google guidelines include more material than listed here, and are used as a
+guide that enables easy decision making about proposed content changes. 
+
+Other useful resources:
+
+- [Google Technical Writing Courses](https://developers.google.com/tech-writing)
+- [GitHub Guides Mastering Markdown](https://guides.github.com/features/mastering-markdown/)
+
 ## Metadata
 
 The layout metadata at the top of the README.md file controls how the tutorial page is published. Write permissions are limited to preserve the structure and contents.
@@ -22,7 +42,7 @@ The layout metadata at the top of the README.md file controls how the tutorial p
 
 Each Cosmos SDK tutorial lives in a self-describing folder: `blog`, `hello-world`, `voter`, and so on.
 
-Two sub-folders are present for each production-ready tutorial:
+Two sub-folders are present for most of the production-ready tutorials:
 
 - A self-describing sub-folder for the app and the rest of the code that runs the tutorial.
 - A `tutorial` sub-folder for the Markdown files (*.md) that build the published tutorial docs.
@@ -31,9 +51,9 @@ Work-in-process tutorials might have content and code in other repos.
 
 ## Who works on the tutorials?
 
-- The Tendermint (All in Bits) DevX team (@fadeev, @lubtd, @ilgooz and other amazing devs that I don't know the GitHub usernames for) develops the tutorial code and dependencies. Don't they do an amazing job?
+- The Tendermint (All in Bits) DevX team develops the tutorial code and dependencies. Our team includes [@fadeev](https://github.com/fadeev), [@lubtd](https://github.com/lubtd), [@ilgooz](https://github.com/ilgooz), [@Pantani](https://github.com/Pantani), and other talented developers. Don't they do an amazing job?
 
-- The Tendermint (All in Bits) EcoDev Engineering team (@toschdev, @lukitsbrian, @barriebyron) manages developer experience and owns the tutorial doc content.
+- The Tendermint (All in Bits) EcoDev Engineering team ([@toschdev](https://github.com/toschdev), [@barriebyron](https://github.com/barriebyron), [@alijnmerchant21](https://github.com/alijnmerchant21, and more incoming team members) manages the developer experience and owns the tutorial doc content.
 
 - The Tendermint (All in Bits) Design team owns the front end and publishing. Be sure to check with @lovincyrus for details about the metadata for layout and publishing tutorials.
 
@@ -58,28 +78,28 @@ Since the deploy preview doesn't work on Draft PRs, follow these steps to previe
 
 1. If you haven't already, clone the tutorials repo to your local machine and change to that directory. For example:
 
-  ```
-  cd ~/github
-  git clone https://github.com/cosmos/sdk-tutorials
-  cd sdk-tutorials
-  ```
+    ```
+    cd ~/github
+    git clone https://github.com/cosmos/sdk-tutorials
+    cd sdk-tutorials
+    ```
 
 2. Local tutorials require JavaScript. If needed, install [npm](https://docs.npmjs.com/cli/v6/commands/npm-install).
 
 3. For each branch you work in, install the npm packages for the SDK tutorials:
 
-  ```
-  npm install
-  ```
+    ```
+    npm install
+    ```
 
 4. Start the local instance of the tutorial build:
 
-  ```
-  npm run serve
-  ```
+    ```
+    npm run serve
+    ```
 
   A successful client compile looks like: `> VuePress dev server listening at http://localhost:8080/ ✔ Client Compiled successfully in 280.71ms success [12:06:28] Build 03d41f finished in 283 ms! ( http://localhost:8080/ )`
 
 5. You can now view the tutorial build on a local web browser. Isn't this fun?
 
-  Tip: On a mac, press the command key and click `http://localhost:8080/` for quick access.
+    Tip: On a mac, press the command key and click `http://localhost:8080/` for quick access.