1. Allows to set a timeout (though still not perfect but way better than before)
2. Allows to have unit tests
3. I also added unit tests for the existing controller code
4. Corrected PHPDoc on IClient
* Register OCP\Capability\IManager at DIContainer
* Add register capabilities to appframework
* Register capabilities in DI way
* Make unit test pass again
* Remove CapabiltiesManager from OCP