Changed text color to white for .active.today TD

**Before**
![image](https://f.cloud.github.com/assets/614532/330190/eda245a2-9bc6-11e2-979b-d1bd29e999f5.png)

**After**
![image](https://f.cloud.github.com/assets/614532/330200/066563b2-9bc7-11e2-9d65-3a74bd2f06dc.png)