Add images
Put office hour and contact info in README
Added missing step in setup: run bundler

The documentation is missing a step that Bundler newbies might not know
to do, which is to run the 'bundle' command before running 'bundle exec
middleman'.
Complete Week 1's index.html.erb page

* Fix footer
Remove 'pull-left' and 'pull-right; to make more semantic
Fix image reference for background image. Reference path wasn't working.
Add base_styles sheet to track universal items like typography.
Use $gray color in header-type tags.
Use $gray in header-type tags.
Add global paragraph styles: line-height and margin.
Declare $gray.
Fix color definition to match example version: 'white' over #FFF.
Remove margin on global h1.