CPE as mixit14 partner. Refactored partners resources.
Sponsor page : link to Mix-IT 2014 sponsoring
Navbar : added Sponsors page.
Fixes mix-it/linkit#71 : (mini) CPE logo in footer
Sponsors: Cloudbees EN i18ned
Sponsors: don't display Supporters section if no supporters for event.
Footer : margin for MPT + fucking responsive. But I can't make content centered in columns :(
Merge pull request #75 from clacote/fix/71-cpe-partner

CPE as mixit14 partner
Fixes mix-it/linkit#57 : "500 people each day" -> "500 people".