Prepare next development iteration

Change-Id: Ic3be5e41da53b585c19563897b7112de33900a7e
KmsHttpEPServer: Fix memory leak

Change-Id: Ia79b09c3fc7612a88c16c7405f648bf7afc33f9e
EventHandler: Avoid a non-valid access to memory

Change-Id: I8ede4fcdf9bbd898c064b5ab5418607646c9f750
MediaSourceImpl: fix memory leak

Change-Id: I12c2cc9cc456c204da0b987a48f2e4c7b87af8e1
valgrind: suppress errors calling lookup_by_name

Change-Id: I8ebee77fef15a06e20edefe5eeceb81b752af31c
Update plugins version

Change-Id: I5180a6fae3d3144bfa3f5ce5c4a63e42e27d61b8
MediaSet: Remove ugly hack

Delete pointer instead of creating a new shared_ptr

Change-Id: I7b6c736821771812353d01515f581e0324a1301f
PlayerEndpoint: Stop player before release it

This way we got extra guarantees that element will be release correctly

Change-Id: Ieac22f6c0af8237565a38a2943ce780769bc6e3c
Prepare release 4.2.4

Change-Id: Ie141547dffe656bf7e57edb0e0e5f81d038c3255