==========================
- Added a simple configuration object for WSGIapplication, available in the
config attribute. Extras modules that use configuration (i18n, jinja2,
sessions) don't require app.config to be set manually anymore. Still, the
`secret_key` key config for sessions, if not defined, will result in an
exception.
- Deprecated webapp2_extras.config, replaced by the simpler app dict.
- Router no longer receives app on construction, for consistency with the
config object. App is set as global before router is initialized.
- Fixed a bug in webapp2_extras.sessions that made it not save the session
when it was empty (like when flashes are popped).
- Added standalone uri_for function, to be used in templates.