GetCropUrl to not use .Url property but get directly from cropper JSON
Merge remote-tracking branch 'origin/HEAD' into 7.1.0-ImageCropper-JeavonWIP
GetCropUrl - needed to get the url from within the json within the check for a crop otherwise a exception can occur
If cropper property editor not in use on umbracoFile then we can use mediaItem.Url
Merge pull request #327 from Jeavon/7.1.0-ImageCropper-JeavonWIP

7.1.0 image cropper - GetCropUrl not using .Url anymore