Agregado carrito con ViewModel para la entrega parcial

app/src/main/java/com/cesanelli/lajusta/MainActivity.java

app/src/main/java/com/cesanelli/lajusta/io/ApiService.java

app/src/main/java/com/cesanelli/lajusta/io/models/Cart.java

...c/main/java/com/cesanelli/lajusta/io/models/CartItem.java

...rc/main/java/com/cesanelli/lajusta/io/models/Product.java

app/src/main/java/com/cesanelli/lajusta/io/models/Token.java

.../main/java/com/cesanelli/lajusta/io/models/TokenBody.java

app/src/main/java/com/cesanelli/lajusta/io/models/Unit.java

app/src/main/java/com/cesanelli/lajusta/ui/CartFragment.java

...ava/com/cesanelli/lajusta/ui/CartRecyclerViewAdapter.java

...src/main/java/com/cesanelli/lajusta/ui/LoginFragment.java

.../main/java/com/cesanelli/lajusta/ui/ProducerFragment.java

...main/java/com/cesanelli/lajusta/ui/ProducersFragment.java

...om/cesanelli/lajusta/ui/ProducersRecyclerViewAdapter.java

...c/main/java/com/cesanelli/lajusta/ui/ProductFragment.java

.../main/java/com/cesanelli/lajusta/ui/ProductsFragment.java

...com/cesanelli/lajusta/ui/ProductsRecyclerViewAdapter.java

.../main/java/com/cesanelli/lajusta/ui/RegisterFragment.java

...ava/com/cesanelli/lajusta/ui/viewmodel/CartViewModel.java

app/src/main/res/layout/fragment_cart.xml