core: Move scheduler to modules

The scheduler component used to be into a "beans" folder, but it is not
different from other components, like "dal" or "bll", so it makes more
sense to have it in the same folder.

Change-Id: I291a87742ddb2d536bd0d11f54515ac531b69659
Signed-off-by: Juan Hernandez <juan.hernandez@redhat.com>