Improved error reporting if the cURL or JSON were to ever fail.
The cache now stores the first dynamic line ("tutoring sessions this week") as well as the list.
Moved the week calculations to be done only if the cache is invalid.
Improved the output of dates in the first line, to show the relevant parts of the date (examples as they will appear: "Sep 30th through Oct 4th"; "Dec 2nd through the 6th"; "Dec 30th through Jan 3rd of 2014"). Weeks are now displayed as the Monday through the Friday of that week.
Added the CSUG logo in place of the text "CSUG" in the second line on the page (tool-tip: "Computer Science Undergraduate Council"; alt-text: "CSUG (logo)").
Added tool-tips to the days of the week shown in the list, containing the day of month (and the relevant parts to define it relative to now; examples "the 30th", "Oct 3rd"; "Jan 6th of 2014").
Using CSS in head to style list items.
Removed an unused JavaScript function.
Removed some unused variables.
Improved comments slightly.