ENYO-1269: fix createFile on Firefox

* ENYO-1269-2: Merge branch 'master' into ENYO-1269-2 (HEAD, origin/ENYO-1269-2, ENYO-1269-2)
* ENYO-1269-2: tweak createFile FormData when running in Firefox
* ENYO-1269-2: remove dead code
* ENYO-1269-2: update enyo so Blob works with oldish firefox
* ENYO-1269: fixed array concatenation

Enyo-DCO-1.1-Signed-off-by: Dominique Dumont <dominique.dumont@hp.com>