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So apparently, it was working, but now the make file isn't allowing this to get installed correctly on SimplyTest.me:
You need to download the FullCalendar plugin and extract the entire contents of the archive into the sites/all/libraries folder of your server.
I initially tested it here:
http://simplytest.me/project/commons?add[]=i18n&add[]=fullcalendar&add[]...
But also on the 7.x-2.0 version here:
http://simplytest.me/project/fullcalendar