Add contribution guide

CONTRIBUTING.md

@@ -0,0 +1,66 @@
+# Contributing
+
+Hey, welcome to the party! 🎉
+
+Thank you so much to contribute to EasyMDE. 😘
+
+
+## Asking questions, suggesting wonderful ideas or reporting bugs
+
+You can [submit an issue️](https://github.com/Ionaru/easy-markdown-editor/issues/new) on this GitHub repository.
+
+
+## Coding
+
+### 📦 Prerequies
+
+You need node.js and npm.
+
+To install them on Debian-based systems:
+
+```bash
+curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
+sudo apt-get install -y nodejs
+echo -e "nodejs version:\t$(nodejs -v) \nnpm version:\t$(npm -v)"
+# check that you have node.js and npm.
+```
+
+For other systems, please [read the official page](https://nodejs.org/en/download/).
+
+
+### 🏗️ Installation
+
+Here we go! 🤠 First, clone this repository:
+
+```bash
+git clone https://github.com/Ionaru/easy-markdown-editor.git
+```
+
+Then install the EasyMDE for development environment with npm:
+
+```bash
+npm install --save-dev
+```
+
+And check that everything is ok by running Gulp:
+
+```bash
+gulp
+```
+
+Yay! You are ready! 🍾
+
+### ⤴️ Creating a pull request
+
+- 1. First, [create a fork of this project](https://github.com/Ionaru/easy-markdown-editor/fork), and copy the https URL (*clone or download* button) of your project (something like https://github.com/YOUR_USERNAME/easy-markdown-editor.git );
+- 2.a If you already cloned and worked on the project: `git remote add source https://github.com/Ionaru/easy-markdown-editor.git`;
+- 2.b otherwise, clone your fork: `git clone https://github.com/YOUR_USERNAME/easy-markdown-editor.git`;
+- 3. create a new dedicated branch `git checkout -b myMergeRequest`;
+- 4. write some nice code and commit your work;
+- 5. check files against the ESLint syntax and build minified versions: `gulp`;
+- 6. push it to a dedicated branch `git push origin myMergeRequest`;
+- 7. got to the [main project page](https://github.com/Ionaru/easy-markdown-editor) and click on the button *Compare and pull request*, then fill the description.
+
+If you want to make other pull requests, go back to the development branch (`git checkout development`), update it (`git pull --rebase source development`), then follow the instructions above from step 3.
+
+Thank you! 💜

README.md

@@ -39,6 +39,7 @@ The editor is entirely customizable, from theming to toolbar buttons and javascr
   - [Useful methods](#useful-methods)
 - [How it works](#how-it-works)
 - [SimpleMDE fork](#simplemde-fork)
+- [Contributing](#contributing)
 - [License](#license)
 
 
@@ -416,6 +417,11 @@ Changes include:
 My intention is to continue development on this project, improving it and keeping it alive.
 
 
+## Contributing
+
+Want to contribute to EasyMDE? Thank you! We have a [contribution guide](./CONTRIBUTING.md) just for you!
+
+
 ## License
 
 This project is released under the [MIT License](./LICENSE).