Experimental theme for frontend with Flat UI

Hey guys,

I've found this nice twitter bootstrap UI kit - http://designmodo.github.io/Flat-UI/ and tried to play with our frontend a bit so that it looks at least a bit less bootstrapish!

Below you can see some screenshots - I also deployed this branch to demo for the moment.

Please keep in mind it's just a proof of concept, I've spent on it ~1,5 hour.

If you like it, we can work on this further, if no - delete the branch. :smiling_imp: 

Let me know what you think, cheers!

![sylius - modern ecommerce for symfony2 - google chrome_002](https://f.cloud.github.com/assets/614970/659149/7feea98e-d667-11e2-90e3-3581781c062c.png)
![sylius - modern ecommerce for symfony2 - google chrome_003](https://f.cloud.github.com/assets/614970/659150/81d8a6aa-d667-11e2-9ca0-54b20313154b.png)
![sylius - modern ecommerce for symfony2 - google chrome_004](https://f.cloud.github.com/assets/614970/659151/84fd754a-d667-11e2-8661-a739e7a810ab.png)
![sylius - modern ecommerce for symfony2 - google chrome_005](https://f.cloud.github.com/assets/614970/659152/891673b6-d667-11e2-82a2-4573c0044f31.png)
![sylius - modern ecommerce for symfony2 - google chrome_006](https://f.cloud.github.com/assets/614970/659153/8a3fa744-d667-11e2-9606-99aaa0c46140.png)
![sylius - modern ecommerce for symfony2 - google chrome_007](https://f.cloud.github.com/assets/614970/659154/8b14fbc4-d667-11e2-93c8-48297a401437.png)
![sylius - modern ecommerce for symfony2 - google chrome_008](https://f.cloud.github.com/assets/614970/659155/8c1264da-d667-11e2-8b36-5eb460f0155f.png)
![sylius - modern ecommerce for symfony2 - google chrome_009](https://f.cloud.github.com/assets/614970/659156/8cf688e0-d667-11e2-87ce-0b4c14d1435a.png)
![sylius - modern ecommerce for symfony2 - google chrome_010](https://f.cloud.github.com/assets/614970/659157/8df3d4d2-d667-11e2-8d02-d94ed12e8183.png)