Add Fusion responsive support

First step is simply to add relevant lines to the .info file.

Doing so will also address the error reported in #1606938: Invalid argument supplied for foreach().

Confusingly, the .info file comments in fusion_starter suggest that adding responsive settings to child themes won't be necessary after #563708: Improve theme_get_setting() and make custom theme settings a true form_alter is fixed:

; Default theme settings for responsive layouts. 
; These can be removed from children themes once inheritance is properly fixed
; in core.  See issue #563708.

but (a) there are no such lines in fusion_core.info and (b) leaving them out of Granada doesn't fix the issue.

So time to copy and paste.