RF: Rename tensor statistics to remove "tensor_" from them.

They are all in the dti module after all.
Merge pull request #203 from arokem/tensor_rename

RF: Rename tensor statistics to remove "tensor_" from them.
NF: new model added for constrained spherical deconvolution and a corresponding test. This is still in progress
TEST updated test for test_csdeconv
cdeconv class returns a fit object
Started example for csd
Updated csd to work with any odf_sphere
TEST updated test2
NF: example with estimated response function from the data added
TEST: added module suite from numpy.testing
work in progress: need to debug odf_deconv
work in progress: need to debug odf_deconv
wip: debuging...
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NF: Sharpening Deconvolution Transform (SDT) works and is debugged. More tests and doc to be written
Added function to transform an odf_sh to sharp odf
Changed dataset of example
TEST: updated and cleanup the tests. Allowed testing with different crossing angles