RF: update Cython dependency

Getting compile errors for Cython 0.17; update dependency to 0.18.
Merge pull request #393 from matthew-brett/update-cython-dependency

RF: update Cython dependency
BF: fix import statement for get_cmap

I think you can't do ``import module.attribute as attribute``, and you
have to do something like ``from module import attribute``.
BF - csd model is fitting coefficients instead of data
TST - added test for regularization sphere with CSD model
RF - Have lambda in csdmodel scale with sqrt sphere size
TST - test default lambda value
TST - added a test for the quality of csd fit with high sh order
DOC - updated docs and variable names to reflect new csd fitting method.
TST - make crossing in high order deconv test more reliably detectable.
TST - update csd-xval test
DOC: The cross-validation example changed with improvements to csdeconv.
Merge pull request #397 from matthew-brett/fix-get-cmap

BF: fix import statement for get_cmap
Merge pull request #8 from arokem/MrBago-bf_csd_fits

DOC: The cross-validation example changed with improvements to csdeconv.
Merge pull request #340 from MrBago/bf_csd_fits

CSD fit issue
BF: fix skiptest invocation for missing mpl

SkipTest is in nose namespace; use numpy testing decorator to apply
skiptest to test neededing matplotlib.
Merge pull request #401 from matthew-brett/continue-no-mpl-fixes

BF: fix skiptest invocation for missing mpl