Cannot upload files with extensions like JPG, pnG, Gif using ['jpg', 'png', 'gif'] allowed extensions array

[AlexUsovich]

Is it possible to implement functionality to allow to upload files with such extensions that can be simply transformed to lower case and then compared to those that defined at allowedExtensions? That can be done at https://github.com/ribizli/ng2-imageupload/blob/master/src/image-upload.directive.ts or another idea to add option like strictMode: boolean that can be true/false. Then if false we can compare extension with a lower case.