Change draw routines to shift by 0.5,0.5 for even images.  Lots of tests failing now (as expected)
(#380)
Merge branch 'master' into #380
Move the fix_center stuff to a helper function.  Also add documentation about the new behavior.
(#380)
Fix spline tests to work with new centering rule
(#380)
Add bounds.trueCenter() method, and flesh out the rest of the Bounds documentation
(#380)
Get test_shapelet.py working
(#380)
Re-fix test_spline.py
(#380)
Fix test_correlatednoise.py
(#380)
Fix test_atmosphere.py
(#380)
Fix most of test_SBProfile.py
(#380)
Fix test_InterpolatedImage.py
(#380)
Fix bug in SBProfile fillKGrid when drawing shifted profiles (or probably any non-radially symmetric profile)
(#380)
Start on test of Scattered image bug that David pointed out
(#380)
Add test that Scattered stamp size is indexed by obj_num (which currently fails)
(#380)
Fix config machinery to work with new centering.  Also make stamp_size index on obj_num for Scattered images
(#380)
Add option to index images by Position in addition to x,y.
(#380)
Updates to demos and config to make them consistent with new centering behavior
(#380)
Make shift, setOrigin, and setCenter take either (x,y) as before or a PositionI parameter
(#380)
Enable the image.index_convention option (default 1)
(#380)
Add unit tests for new index_convention option
(#380)