Unified command execution and unit tests

- All arguments inits moved to own clases
- Added unified way to execute commands
- Unit test structure and very basic tests
- Command line script to test coverage
- Argument parsers moved to corresponding commands
- Automatic parsers and command mapping

Change-Id: Id099d14702d9590729583dfd9574bd57022efac5
Related-PROD: PROD-28199
diff --git a/cfg_checker/helpers/errors.py b/cfg_checker/helpers/errors.py
index ca8a8da..1f962eb 100644
--- a/cfg_checker/helpers/errors.py
+++ b/cfg_checker/helpers/errors.py
@@ -200,7 +200,7 @@
         # Detailed errors
         if self.get_errors_total() > 0:
             # create list of strings with error messages
-            for _idx in range(1, self._index - 1):
+            for _idx in range(1, self._index):
                 _list.append(self._format_error(_idx))
                 _list.append("\n")
         else: