Update readme

Bugfix debug logging during update
unrar-free is now also recognized for displaying unrar version in about section, removed unused not configured string

cps/updater.py

@@ -214,7 +214,7 @@ class Updater(threading.Thread):
             if not os.path.exists(dst_dir):
                 try:
                     os.makedirs(dst_dir)
-                    log.debug('Create directory: {}', dst_dir)
+                    log.debug('Create directory: {}'.format(dst_dir))
                 except OSError as e:
                     log.error('Failed creating folder: {} with error {}'.format(dst_dir, e))
                 if change_permissions:
@@ -233,7 +233,7 @@ class Updater(threading.Thread):
                         permission = os.stat(dst_file)
                     try:
                         os.remove(dst_file)
-                        log.debug('Remove file before copy: %s', dst_file)
+                        log.debug('Remove file before copy: {}'.format(dst_file))
                     except OSError as e:
                         log.error('Failed removing file: {} with error {}'.format(dst_file, e))
                 else: