Improvement of post date management / upload folder

Right now, the plugin has trouble picking a folder, especially for draft/pending posts which do not have a post_date_gmt set.

Proposal :
Replace src/ImageUploader.php:161
$upload_dir = wp_upload_dir(date('Y/m', $this->post->post_date_gmt ? strtotime($this->post->post_date_gmt) : time()));
By :

if( get_option( 'uploads_use_yearmonth_folders' ) ) {
            if( strtotime( $this->post->post_date_gmt ) > 0 ) {
                $post_time = strtotime( $this->post->post_date_gmt );
            }
            elseif( strtotime( $this->post->post_date ) > 0 ) {
                $post_time = strtotime( $this->post->post_date );
            }
            else {
                $post_time = time();
            }
            $upload_dir = wp_upload_dir( date( 'Y/m', $post_time ) );
        }
        else {
            $upload_dir = wp_upload_dir();
        }

This code respect the choice of using yearmonths folder, and tries to get the best possible date from the post