Forward declare SfxFoundCacheArr_Impl and SfxFoundCache_Impl in bindings.hxx.

And remove #include <boost/ptr_container/ptr_vector.hpp> from here.

Change-Id: I7624444b60ee19f0b5b19e7a7aab0210ddf90d7c
Same with SfxUnoControllerArr_Impl.

Change-Id: I927621de8f4c486ef0f77ec6c8da336f36b38b3e