container is now fluid (80%), without max-width

In order to fix issue #8 I've removed max-width to .container and made it fluid with a relative width (80%).
Now the timer is correctly aligned on big screen:
![screen shot 2014-08-22 at 11 28 40](https://cloud.githubusercontent.com/assets/4426735/4009011/bd6dae2e-29de-11e4-8ebf-17a07db2e84e.png)