Coinffeine/coinffeine — pull request #174 by sortega (2014-06-12 20:19:16+00:00)
Title: Implement TopUpStepPane

**Description:** complete the wizard with the last step, `TopUpStepPane`. Add zxing library for QR code generation.
**Testing:**
![image](https://cloud.githubusercontent.com/assets/259587/3263172/cfde3f94-f26e-11e3-9da8-a841ece5ffb0.png)