oos_util_apex.create_session can't handle preserved case usernames

[mennooo]

We use usernames with preserved case in our application.
So we need to pass p_preserve_case => true to apex_custom_auth.post_login.

Solution: add p_preserve_case as formal parameter to oos_util_apex.create_session.

[martindsouza]

Commit done as 3ba2de5