Update contact page layout

Updated the contact page so that the information is laid over the background
image.
added high res images for keyconnections, rightshift, and amazon. There is also a lower res placeholder for windows azure
background image for contact page
resized super large sponsor images to be 100px high as their large size
created scaled copies of windows azure, rightshift and key connections for sponsors page
higher res github logo, rescaled event sponsor images
updated github text to be in a paragraph rather than tagline
changed tagline formatting and spacing on sponsors page
updated the spacing on the speakers info page
Merge branch 'scaleconf2013' into gh-pages