Android App：Daily Money Change Log 2012/05/14

This project is a fork of original Daily Money project hosted on github by Dennis Chen
https://github.com/dennischen/daily-money

1. bug fixing for installment.
2. only keep backups last 7 days when execute daily backup.
3. bug fixing for pie chart.

1. 分期付款處理的問題修正。
2. 每日自動備份時，只保留最近七天的資料。
3. 圓餅圖問題修正。