The previous documentation said this:
g_type_add_interface_static:
"Adds the static interface_type to instantiable_type"
g_type_add_interface_dynamic:
"Adds the dynamic interface_type to instantiable_type"
The above suggests that if one is adding a static interface to a dynamic
object, one should use g_type_add_interface_static because the interface
is static, but the code and usage (with the newly added
G_IMPLEMENTS_INTERFACE_DYNAMIC) imply that this is wrong, and that
what matters is whether the *instanciable_type* is dynamic or not.
Hence this patch moves the "static" and "dynamic" words close to
"instantiable_type".
Closes issue #259