swig: Use alloca() to reserve stack variables used in typemaps.
swig: Use alloca() to reserve stack variables used in typemaps.

Otherwise, swig sometimes places variables inside scopes, and
retaining pointers to these variables causes problems.

johnty/libmapper,libmapper/libmapper,davidhernon/libmapper-admin2,johnty/libmapper,johnty/libmapper,davidhernon/libmapper-admin2,radarsat1/libmapper,radarsat1/libmapper,davidhernon/libmapper-admin2,libmapper/libmapper,malloch/libmapper,malloch/libmapper,davidhernon/libmapper-admin2,libmapper/libmapper,radarsat1/libmapper,malloch/libmapper,johnty/libmapper,libmapper/libmapper,radarsat1/libmapper,davidhernon/libmapper-admin2,radarsat1/libmapper,malloch/libmapper,malloch/libmapper,libmapper/libmapper,johnty/libmapper,malloch/libmapper,libmapper/libmapper