Added more unit tests, improved style and fixed:
- Failed behaviour of redirects
- Incorrect behaviour on feed retrival failure
- Ensured rss cache clear for unit test setup
To replace unmaintained magipie. Simplepie is actively maintained has some
nice features such as feed autodisovery. Implemented a simple extended class
which uses the Moodle core curl class from filelib.
Added unit test using the moodle.org sample files. Please note these tests will
fail if moodle can't make http connections out, so ensure proxy settings
etc are correct.
