Use 'glibtoolize' on Mac OS X

Although I wonder if a simple `autoreconf -if` wouldn't work.

Based-on: nandub/gale-old@057b632cc454e24d1e4a8c1c1903de9ab24a4f3d
Call GC_INIT() on startup

Based-on: nandub/gale-old@5802be676c6b3f02976d763663d4353dbfd686c3
Fixes: nandub/gale-old #1