Use correct config version default number (#1305 by @buhtzz)

"config.Config.CONFIG_VERSION" sets the current default version of the config files used by the latest stable BIT release is 6. This fix makes sure that this number is used by default for (empty) config files that don't specificy "config.version" by their own.

In the wild, normal users should never encounter this problem except in some edge cases. But it is highly relevant for unittesting where some of tests do use empty config files.

common/config.py

@@ -49,7 +49,9 @@ class Config(configfile.ConfigFileWithProfiles):
     APP_NAME = 'Back In Time'
     VERSION = '1.3.2'
     COPYRIGHT = 'Copyright (C) 2008-2022 Oprea Dan, Bart de Koning, Richard Bailey, Germar Reitze'
+
     CONFIG_VERSION = 6
+    """Latest or highest possible version of Backin Time's config file."""
 
     NONE = 0
     AT_EVERY_BOOT = 1
@@ -195,11 +197,16 @@ def __init__(self, config_path = None, data_path = None):
             else:
                 os.rename(old_path, self._LOCAL_CONFIG_PATH)
 
+        # Load global config file
         self.load(self._GLOBAL_CONFIG_PATH)
+
+        # Append local config file
         self.append(self._LOCAL_CONFIG_PATH)
 
-        #?Internal version of current config;;self.CONFIG_VERSION
-        currentConfigVersion = self.intValue('config.version', 5)
+        # Get the version of the config file
+        # or assume the highest config version if it isn't set.
+        currentConfigVersion \
+            = self.intValue('config.version', self.CONFIG_VERSION)
 
         if currentConfigVersion < self.CONFIG_VERSION:
             # config.version value wasn't stored since BiT version 0.9.99.22