(docs) Add Contributing guide

Author: feimosi

CONTRIBUTING.md

@@ -0,0 +1,64 @@
+# Contributing to baguetteBox.js
+
+Please read these guidelines before contributing code.
+
+## :nut_and_bolt: Setting up the development environment
+- Fork and clone the repository
+- `npm install`
+- `npm start`
+- Demo page with live reload is available at `localhost:3000`
+
+## :bug: Fixing a Bug
+When fixing a bug please make sure to test it on as many browsers as possible (see: [Compatibility](./README.md#compatibility)). If you are not able to do so, mention that in a PR comment, so other contributors can do it.
+
+## :tada: Proposing a Change
+When implementing a feature please create an issue first explaining your idea and asking whether there's need for such a feature.
+Remember the script's core philosophy is to stay simple and minimal, doing one thing and doing it right.
+
+## :pencil: Before you open a Pull Request
+- Follow Git best practices (especially use meaningful commit messages).
+- Describe thoroughly you work in a PR comment.
+- Be patient and understanding. It's a side project, done in free time.
+
+Thank you to everyone who has contributed to baguetteBox.js!
+
+## :rocket: Releasing the next version
+
+#### :heavy_exclamation_mark: This should be done only by core contributors :heavy_exclamation_mark:
+
+Build the script
+```sh
+gulp build
+git add --updated
+git commit -m "Build update"
+```
+
+Bump the version
+```sh
+gulp release # or gulp patch
+git add --updated
+git commit -m "v1.8.0"
+```
+
+Push changes
+```sh
+git push
+```
+
+Add a tag
+```sh
+git tag v1.8.0
+git push --tags
+```
+
+Deploy the new demo page
+```sh
+gulp deploy
+cd ./publish
+git push
+```
+
+Publish the new version to `npm`
+```sh
+npm publish
+```

README.md

@@ -15,9 +15,9 @@ Simple and easy to use lightbox script.
 ## Features
 
 * Written in pure JavaScript, no dependencies required
-* Multiple-gallery support, allows custom options for each
+* Multiple-gallery support allows custom options for each
 * Supports swipe gestures on touch-screen devices
-* Full screen mode available
+* Full-screen mode available
 * Modern and minimal look
 * Image captions support
 * Responsive images
@@ -158,16 +158,16 @@ If you have 1366x768 resolution baguetteBox.js will choose `"img/medium/2-1.jpg"
 * Opera 12+
 * Safari 5+
 
-## Notes
+## Contributing
 
-Feel free to report any issues!
+Feel free to report any issues! If you wish to contribute by fixing a bug or implementing a new feature, please first see [CONTRIBUTING](./CONTRIBUTING.md).
 
 ## Credits
 
 Creation of `baguetteBox.js` was inspired by a great jQuery plugin [touchTouch](https://github.com/martinaglv/touchTouch).
 
 ## License
 
-Copyright (c) 2016 [feimosi](https://github.com/feimosi/)
+Copyright (c) 2017 [feimosi](https://github.com/feimosi/)
 
 This content is released under the [MIT License](https://opensource.org/licenses/MIT).