Liquid assets screen

Initial implementation of the screen.. It have 3 pieces:

1. A donut chart
2. A summary of the expenses
3. A ExpandableListView for listing the expenses

![image](https://cloud.githubusercontent.com/assets/1507064/3520071/551a437a-0727-11e4-9322-ca100bcac6e1.png)

/cc @josemontesdeoca @amitbharadwaj