New Functions

Two new functions have been added:

listIngredients:  a function that lists all the ingredient a user has.  This is the best I could do. calling a simple java line such as:

```javascript
var key1 = Math.floor(Math.random() * arr.length);
var key2 = Math.floor(Math.random() * arr.length);
var key3 = Math.floor(Math.random() * arr.length);
```
get all three keys and send them to the Recipe API.


isUser:  a function that sees if the email entered in registration is already there, if it is, it returns a user Object with the email, else it returns a blank user object.