This filter is builds the path for the dashboard profile image. The
path points to a different icon in the /images/icons directory
depending on what time and day it is.
There is no major functionality addition with this code. It just a
little sprinkle of cuteness for the user of the site.
I'm going to try this with Python and Django first. Because it's not
my personal project, it might be better to use a language which is
more mainstream. It should reduce the 'Bus Factor'.