STYLE : Add the exception message when json reading raises an error

python_src/diapotb/ConfigFile.py

@@ -210,8 +210,9 @@ class ConfigFile():
                 self._data_config = json.load(f)
 
         except Exception as err:
-            logger.critical("Impossible to read or load JSON configuration file : {err}. Check its path and content."\
-                            .format(err=self._config_file))
+            logger.critical("Impossible to read or load JSON configuration file : {name}." \
+                            "Check its path and content. For your information, exception is \n : {err}"\
+                            .format(name=self._config_file, err=err))
             quit()
 
         self._validate_json()