Merge pull request #2 from etoile/gh-pages-tweaks

Merged recent Eric's changes for the website
Further optimized the layout for small sizes (especially small tablet sizes)

Fixed download icons/buttons to be scaled down or up based on the page
size.
Fixed icons not on the same line in Download section for sizes below ~40px
Expressed h1 margin top in the enclosing container padding top
Fixed padding top for #splashline in footer
Fixed incorrect column classes in User experience section
Reworked Contacts page (still needs some work)
Added links to Contact pages and minor tweaks to margin or padding in the CSS
Used section markup to declare sections rather than div

Adjusted section padding on small device sizes.
Fixed vertical space that appears between stacked columns in footer at small sizes
Border tweaks for #small-tagline in colored sections
Fixed last column space at the bottom in the Community section
Color, space and text consistency tweaks in Download section

Download section now matches Features section much more closely.
Styled links and reworked Download section a bit

Added placeholder elements for screenshots.

Added some new links.
Cut tagline a bit in Framework section and added 'Favor JSON to export'
Explicitly say a preview release must not be in production and its API remains unstable
Mention several important features are missing in Framework section
Tweaked two column layout to have a bigger gutter if needed
Underline links with a solid border rather than a dotted one
Updated my bio