NF: Find the closest vertex on a sphere for an input vector.
BF + NF: Implement find_closest for Hemisphere.
Account for antipodal symmetry as appropriate for Sphere/Hemisphere.
TST: Demonstrate that this is scale-invariant.
PEP8: whitespace between functions.
Merge pull request #483 from arokem/find_closest

NF: Find the closest vertex on a sphere for an input vector.
TEST: compare against different energy profile with SSE2
Export build flags to __config__.py
TEST: use exported build flags to select oracle energy profile
TEST: skip regression tests when SSE2 is not supported
BF: apparently, 'has_key(...)' was removed from dict in python3
Generate the config file earlier
HACK: generate __config__ module as a cython extension to make sure it is generated before it is moved to the module install directory
Remove __config__.pyx, will be auto-generated