README: add basic mocha setup instructions

Update README with instructions on how to configure `npm test`
to run unit tests using mocha.

Author: pulkitsinghal

README.md

@@ -9,9 +9,31 @@ The following helpers are designed to generate [mocha] tests against
 
 ## install
 
-```sh
-npm install loopback-testing --save-dev
-```
+1. `npm install loopback-testing --save-dev`
+2. Assuming you started with a clean template/project generated by `slc loopback`
+  1. If you have mocha installed as a global npm module that's great! Simply update `<your_project>/package.json` with:
+
+    ```
+    {
+      ...
+      "scripts": {
+        ...
+        "test": "mocha"
+      }
+    }
+    ```
+  2. Otherwise, you can utilize the mocha library within the `loopback-testing` testing module:
+
+    ```
+    {
+      ...
+      "scripts": {
+        ...
+        "test": "./node_modules/loopback-testing/node_modules/.bin/mocha"
+      }
+    }
+    ```
+3. Run `npm test` to execute any tests under the `test` directory.
 
 ## basic usage
 
@@ -29,6 +51,7 @@ Use the `loopback-testing` module to generate `mocha` tests.
 ```js
 var lt = require('loopback-testing');
 var assert = require('assert');
+var app = require('../server/server.js'); //path to app.js or server.js
 
 describe('/products', function() {
   lt.beforeEach.withApp(app);
@@ -38,7 +61,7 @@ describe('/products', function() {
       assert.equal(this.res.statusCode, 200);
     });
 
-    lt.givenModel('product');
+    lt.beforeEach.givenModel('product');
     it('should respond with an array of products', function() {
       assert(Array.isArray(this.res.body));
     });