More structure changes; User icon made more visually appealing.
Added more tumblr specified content.
Added basic post div.  Rounded corners of sidebar to match posts.
Removed temporary colors.

Removed the colors from divs that should be invisible, which were used to better visualize
the structure as it was being created.  Added user-specified tumblr color variables for
the posts and footer.  Default color has been set to #F1F1F1, like sidebar already was.
Made Footer more robust and other small changes

Made the information displayed in the footer more robust.  Added to option to disable the footer.
Added a link to the theme's Github repo to the footer.  Discovered bug:
Sticky footer is no longer sticky.

Made background image fixed.

Made user icon and blog title links to the blog's main page.