Making working with child themes easier

I added checks to see if Reverie functions have already been declared so they can easily be overridden in child themes — since child theme ```functions.php``` is loaded before the parent's, you can declare the same function names to override what the original ones would do.

I also changed the URI the base stylesheets use, so they refer to the parent theme stylesheets and not a nonexistent file in a child theme.