Now converting images on live server, modulus error

The issue was that my modulus servo was running some older software. I
asked the guys and they upgraded my servo, so ffmpeg became accessible.
Converting of images is now functioning, as is a pre-check to see if the
the gif is already downloaded. Then dynamic replacement is working.

Also: switched Giphy searches to return mp4s to the gifwindow with a
fallback gif, gif is sent to the message box for conversion. Mp4s are
playing on hover, this should reduce page load & response times
significantly.