Fix center image

[mokraemer]

if the resulting canvas element is not of the same size as the picture, the picture was not centered in the canvas element

[mandaputtra]

do this fix #419 ?

[mokraemer]

I would say "yes". If I use our patched version (https://static.qmsystems.de/js/lib/croppie.js), I can't reproduce the issues I see with the original lib.
Since this is the first time I use git, not all patches from obove apply to this FR/bug.

[vandensudarsono]

it seem your changes is not included in v.2.6.4 version.

[mokraemer]

yes, no one wants to merge...