BLD: Do not generate cython on clean. Closes #1852.
Merge pull request #2006 from jseabold/fix-cythonize

BLD: Do not generate cython on clean. Closes #1852.
FIXUP/WIP: Refactor to use generic data handling
ENH: Allow more general param_names in data handling
ENH: Allow attachment of generic names.
ENH: Refactor to allow wrappers to work.
ENH: Handle the generic 2d case.
ENH: Wrap 2d attributes
REF: Return DataFrame instead of dict.
TST: Fix tests for refactor
STY: Rename attributes