SIFD-9 adding a clear link so that if a file is selected by mistake it can be cleared by the user, this doesn't work on Chrome and Firefox on Ubuntu but the same JavaScript works using jsFiddle on Windows Firefox.  Checking the code in to see if I can test it successfully on Windows with IE (jsFiddle doesn't work on IE)
Merge branch 'master' of https://github.com/Det-Kongelige-Bibliotek/ADL