Verify that all stubs have a return type

Define Stringable with __toString():string method

Remove the deprecated reflection export methods

Closes GH-5188

Revert "Replace @param annotations with type declarations"

This reverts commit c31029f335ca1b453af799805c43c37e959ad555.

Replace @param annotations with type declarations

Always invoke zpp in ReflectionProperty::getValue/isInitialized

Make sure we still perform a zpp check for the static case, and
also always enforce that the parameter is ?object. Otherwi

Always invoke zpp in ReflectionProperty::getValue/isInitialized

Make sure we still perform a zpp check for the static case, and
also always enforce that the parameter is ?object. Otherwise we
violate the specified signature.

show more ...

Rename reflection stub file

Where possible, the stub file should match the name of the C file,
so that the build system integration automatically recompiles it.