Fix AS2MovieClip's native _insertChildAtDepth to assign the AS2 reflection of the added child to `name` instead of the AS3 MovieClip
Change AVM1 ActionCallFunction to ignore non-function targets

As per spec and Flash's behavior, not sanity.
Change AVM1 ActionSetMember to ignore non-existing target objects

As per spec and Flash's behavior, not sanity.
Change AVM1 property resolution to ignore non-existing target objects

As per spec and Flash's behavior, not sanity.
Merge pull request #1437 from tschneidereit/nat

AVM1 fixes