docs: add contributing file

CONTRIBUTING.md

@@ -0,0 +1,36 @@
+# How to contribute to this repository
+Create a fork of this repository and check it out. 
+
+To make everything work you need to symlink the src directory to the app folder once. You can do this manually or by running `npm run link-mod`. 
+
+Once this is done you can run `npm start` to start the development server.
+
+If you implement a new feature it is always a good idea to also add an example of it to the demo application.
+
+## Commit guidelines
+In general this repo tries to adhere to the [angular commit guidelines](https://github.com/angular/angular/blob/master/CONTRIBUTING.md#commit).
+
+## Dev tasks
+There are several scripts defined in the package.json
+
+`npm start`: Starts the development server.
+
+`npm run` **test-watch**: Runs the unit tests via karma.
+
+`npm run` **test**: Runs the unit tests once.
+
+`npm run` **test-coverage**: Runs the unit tests with a coverage report.
+
+`npm run` **build**: Creates a compiled version of your library inside the dist folder.
+
+`npm run` **demo.deploy**: 
+Builds the demo app to demo/dist, copies the readme to it and publishes everything to github pages.
+
+`npm run` **release.changelog**:
+Creates a changelog based on the [angular commit conventions](https://github.com/angular/angular.js/blob/master/CONTRIBUTING.md).  
+
+`npm run` **link-mod**: Creates a symlink to the module inside the demo/src folder. This is required for compiling the app with aot.
+
+`npm run` **lint**: Lints all demo and library files
+
+`npm run` **e2e**: Runs the end2end tests.

README.md

@@ -83,3 +83,5 @@ import {Angular2PromiseButtonModule} from 'angular2-promise-buttons';
 export class MainAppModule {
 }
 ```
+## Contributing
+Contribution guidelines: [CONTRIBUTING.md](https://github.com/johannesjo/angular2-promise-buttons/blob/master/CONTRIBUTING.md)