Add CONTRIBUTING.md and PR template (#150)

* Fix typo

* Create CONTRIBUTING.md

* Create PULL_REQUEST_TEMPLATE.md

* Remove changelog line

.github/CONTRIBUTING.md

@@ -0,0 +1,39 @@
+## How to contribute
+
+Thank you for your interest in contributing to Pattern Manager by WP Engine! There are many ways to contribute to this project.
+
+### File issues
+
+Contribute bug reports or feature suggestions as [GitHub Issues](https://github.com/studiopress/pattern-manager/issues). Please be sure to search to see if your issue or suggestion already exists prior to opening a new issue.
+
+### Contribute code
+
+We recommend that you first [create an issue](https://github.com/studiopress/pattern-manager/issues/new) to propose and discuss major changes before working on them.
+
+[Fork](https://help.github.com/en/articles/fork-a-repo) the [Pattern Manager repository](https://github.com/studiopress/pattern-manager) to your own GitHub account, then clone it to work on locally:
+
+    git clone git@github.com:you-username/pattern-manager.git
+
+Create a new branch to work on your changes. New branches should be forked from the `main` branch.
+
+    git checkout -b feature/your-new-feature
+
+Make your changes and commit your code.
+
+When you're ready, [create a pull request](https://github.com/studiopress/pattern-manager/pulls) to outline and contribute your changes.
+
+To increase the chance that your pull request is approved:
+
+* Lint your code to check that it conforms to WordPress standards. Learn more about the [developer tooling to help lint your code](https://github.com/studiopress/pattern-manager/wiki/For-Developers#linting-code).
+* In commit messages or pull request text, always clearly describe the problems your code solves or the improvements it brings.
+* Do not increment the plugin version as part of your pull request. We'll take care of this for you prior to each release.
+
+### Contributor License Agreement (CLA)
+
+All external contributors to WP Engine products must have a signed Contributor License Agreement (CLA) in place before the contribution may be accepted into any WP Engine codebase.
+
+1. [Submit your name and email](https://wpeng.in/cla/)
+2. 📝 Sign the CLA emailed to you
+3. 📥 Receive copy of signed CLA
+
+❤️ Thank you for helping us fulfill our legal obligations in order to continue empowering builders through WordPress.

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,17 @@
+## Tasks
+
+- [ ] I have signed a [Contributor License Agreement (CLA)](https://github.com/studiopress/pattern-manager/wiki/For-Developers#contributor-license-agreement-cla) with WP Engine.
+
+### Summary of changes
+<!-- A short but detailed summary of the changes. -->
+
+### Related Issues
+<!-- Fixes #xxx. -->
+<!-- See #xxx. -->
+
+### How to test
+<!-- Detailed steps to test this PR. -->
+1. 
+
+### Notes & Screenshots
+<!-- Additional information for reviewers. -->

README.md

@@ -90,7 +90,7 @@ Yes, you will need to have WordPress 6.1 or later installed to take advantage of
 
 ## Screenshots
 
-1. A dedicated inferface to browse, design, build, and save WordPress pattern files.
+1. A dedicated interface to browse, design, build, and save WordPress pattern files.
 2. Easily assign pattern categories, keywords, descriptions, and more.
 
 ## Changelog