Add qrcode generator

Added qrcode generator with this lib https://github.com/davidshimjs/qrcodejs

screenshots:
Standart profile page:
![2014-02-24 8 40 54](https://f.cloud.github.com/assets/426427/2242748/85debfaa-9d0e-11e3-8c10-bcabe20b8a3c.png)

After Show secret key button:
![2014-02-24 8 40 48](https://f.cloud.github.com/assets/426427/2242749/85e08d76-9d0e-11e3-91a1-9688cdedf9b4.png)

after show qrcode link:
![2014-02-24 8 40 42](https://f.cloud.github.com/assets/426427/2242750/85e281ee-9d0e-11e3-9612-a0b29a6f96d8.png)