imrpoved description to test on a map

CONTRIBUTING.md

@@ -7,5 +7,6 @@ Follow these steps to get up and running:
 1.  clone the repository
 2.  run `npm install`
 3.  run `npm start`
-4.  open `index.html` in your browser
-5.  run `npm run cypress` to launch the test suite (also nice for TDD).
+4.  run `npm run cypress` to launch the test suite (also nice for TDD)
+5. Launch developing.spec.js, it will open Chrome with a map and leaflet.pm where you can test the changes you make, manually and with the test suite
+6. In case you need to write tests for your new feature, create a separate *.spec.js file for your tests or add them to an existing one when appropriate

cypress/integration/developing.spec.js

@@ -0,0 +1,7 @@
+describe('Opens Testing Environment', () => {
+  const mapSelector = '#map';
+
+  it('opens a map in a browser', () => {
+
+  });
+});