Removal of CSS for Side Panels

No longer using the side panels so don't need CSS for them.
Fixing Images for 508 compliance

Removing 'background-images' hackery... Putting images in HTML for alt-tags and screen readers.
Added NASA logo
Satellite Hover now Modal

Changed the Satellite Hover to be a modal to match rest of the theme.
Performance Enhancement

Added javascript Image Pre-loader for performance enhancement.
Changed Alt Tag for Close Buttons

Changed the alt tag for 508 compliance and better understanding.
Tweaks and Cleaning

Cleaned up some useless CSS and made some tweaks to modal positioning.
Remove Debugging

Had console log for debugging…