Update __init__.py
Documentation added regarding support for upper case file extensions.
@@ -106,6 +106,8 @@ def load_file(filename,
`database_format` is one of ``'arxml'``, ``'dbc'``, ``'kcd'``,
``'sym'``, ``cdd`` and ``None``. If ``None``, the database format
is selected based on the filename extension as in the table below.
+ Both lower case/upper case extensions are supported, they are
+ each mapped to the same database format.
+-----------+-----------------+
| Extension | Database format |
