Added npy_object.h, the start of the core library object model.
Added npy_object.h, the start of the core library object model.

jasonmccampbell/numpy-refactor-sprint,teoliphant/numpy-refactor,jasonmccampbell/numpy-refactor-sprint,teoliphant/numpy-refactor,jasonmccampbell/numpy-refactor-sprint,teoliphant/numpy-refactor,teoliphant/numpy-refactor,teoliphant/numpy-refactor,jasonmccampbell/numpy-refactor-sprint