add links to opam
Merge pull request #249 from amirmc/redesign

add links to opam
Add an edit icon to the navigation bar.
Align the edit button with the bottom of the "OCaml" logo.
Make the background of the edit button transparent.

It seems that some browsers do not see it is the same color as the
background of the navigation bar.
Tweak CSS so that the edit button works when the nav bar is collapsed.
Remove the "Edit this page" link in the footer.
Add a link for "hundreds of packages" on the front page.
make download buttons consistent - resolves #201
Merge pull request #252 from amirmc/redesign

make download buttons consistent - resolves #201
add link to 100lines to front page
Merge pull request #260 from amirmc/redesign

add link to 100lines to front page
Planet: Position better the RSS imgage & add tooltip.
Planet: Try to make the "Read more" buttons lighter.
Planet: decrease the top padding of the RSS image.
add cryptosense to companies page - closes #261
add default image and tweak companies page
rework books page to improve layout and content

resolves #259 by moving and restricting image sizes,
grabbing excerpts where needed and adding
placeholder images when no cover is available.
Merge pull request #262 from amirmc/books

Rearrange books page and tweaks to company page
tweaks to books page