BUG: fix python 2.4 build.
BUG: fix python 2.4 build.

Move NUMPY_API tag just above neighborhood iterator ctor, as comments in
between cause parse errors on 2.4.

git-svn-id: 77a43f9646713b91fea7788fad5dfbf67e151ece@7175 94b884b6-d6fd-0310-90d3-974f1d3f35e1

teoliphant/numpy-refactor,jasonmccampbell/numpy-refactor-sprint,teoliphant/numpy-refactor,Ademan/NumPy-GSoC,jasonmccampbell/numpy-refactor-sprint,chadnetzer/numpy-gaurdro,illume/numpy3k,illume/numpy3k,chadnetzer/numpy-gaurdro,Ademan/NumPy-GSoC,chadnetzer/numpy-gaurdro,jasonmccampbell/numpy-refactor-sprint,jasonmccampbell/numpy-refactor-sprint,Ademan/NumPy-GSoC,teoliphant/numpy-refactor,teoliphant/numpy-refactor,illume/numpy3k,Ademan/NumPy-GSoC,illume/numpy3k,teoliphant/numpy-refactor,chadnetzer/numpy-gaurdro