service: fixup shared_from_this saga for setOwner/setParent.

We now catch the bad weak ptr and create the shared_ptr
ourselves. This is allowed since we know that it is stored
in the other Service and not destructed at the end of the
function.

Signed-off-by: Ruben Smits <ruben.smits@intermodalics.eu>
scripting: remove some obsoleted keywords

call was a duplicate, sync/async no longer relevant and
time was too restrictive, since it's only used in a very
specific syntax.

Signed-off-by: Ruben Smits <ruben.smits@intermodalics.eu>