Add option to pass acceptable mime types to

MD_STD_IN::move_uploaded_file

src/MD_STD.php

@@ -675,7 +675,7 @@ public static function levenshtein(string $str1, string $str2):int {
      */
     public static function string_to_color_code(string $str):string {
 
-        $code = substr(dechex(crc32($str)), 0, 6);
+        $code = \substr(\dechex(\crc32($str)), 0, 6);
         return $code;
 
     }
@@ -689,11 +689,11 @@ public static function string_to_color_code(string $str):string {
      */
     public static function check_is_writable(string $dir):void {
 
-        if (is_dir($dir) === false) {
+        if (\is_dir($dir) === false) {
             throw new MDFileDoesNotExist("Directory " . $dir . " does not exist");
         }
 
-        if (is_writable($dir) === false) {
+        if (\is_writable($dir) === false) {
             throw new MDFileIsNotWritable("Directory " . $dir . " is not writable");
         }