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

![screen shot 2014-07-08 at 10 05 17 pm](https://cloud.githubusercontent.com/assets/1507064/3520078/760cb4c8-0727-11e4-8861-3dd2d845f762.png)

/cc @josemontesdeoca @amitbharadwaj