FileRepository will automatically warn when it's initialized but no upload adapter was enabled. Closes #58. (29aa315)for...of loop on native FileList because Safari and Edge do not support Symbol.iterator for it yet. Closes #35. (f4efd9b)ImageUploadButton#isEnabled to ImageUploadCommand#isEnabled. Closes #43. (ba6de66)ImageUploadCommand now accepts insertAt position which allows customizing where the image will be inserted. Closes #45. (b90c8d7)UploadImageCommand doesn't optimize the drop position itself anymore. Instead, a separate findOptimalInsertionPosition() function was introduced.UploadImageCommand doesn't verify the type of file anymore. This needs to be done by the caller.