TST: spatial: bump test tolerance
BUG: spatial/qhull: work around issues on Python 2.4
GEN: spatial/qhull: regenerate
ENH: spatial/qhull: upgrade Qhull to version 2012.1
ENH: spatial/qhull: use qh_QHpointer
BUG: spatial/qhull: include correct header
GEN: spatial/qhull: regenerate files
ENH: spatial/qhull: deal with swapping Qhull global state

This allows functionality that requires keeping the Qhull state around,
such as on-line addition of new points.
GEN: spatial/qhull: regenerate files
ENH: spatial/qhull: add support for incremental construction
GEN: spatial/qhull: regenerate files
BUG: spatial/qhull: straighten out issues with the incremental mode

Fix a bug in point ID maintenance.  The triangulation needs to be told
that it is invalidated.  Also, add an option to do a restarted operation
in the middle of an incremental one.
TST: spatial/qhull: add tests for the incremental mode
GEN: spatial/qhull: regenerate files
DOC: update release notes re incremental qhull mode
BUG: spatial/qhull: don't clobber facet.center in get_voronoi_diagram
GEN: spatial/qhull: regenerate files
BUG: spatial/qhull: fix function prototype
GEN: spatial/qhull: regenerate files
TST: spatial/qhull: test qhull instance closing, too