- Added changes in README

- Migrated changes in main.c to tcl backend
- TCL Demo did not honor the specified options
- Added "static" to function "is_stackable" in frontend/main.c. This is an interrim solution, see E-Mail.

frontend/main.c

@@ -397,7 +397,7 @@ int is_fullmultibyte(struct zint_symbol* symbol) {
 
 /* Indicates which symbologies can have row binding
  * Note: if change this must also change version in backend/common.c */
-int is_stackable(const int symbology) {
+static int is_stackable(const int symbology) {
     if (symbology < BARCODE_PDF417) {
         return 1;
     }