Added a notebook that shows how the WM mask was made.
Added markdown documentation in Figure1 notebook.
Added functions for calculating and displaying squared error as well as its corresponding tests.
Altered log_prop_val to allow model fitting of the SFM's dispersion index
Some functions for creating scatter density plots as well as some various fixes.
Changed separate_bvals and test so it would output the rounded and scaled b values.
Changed class init and response function to take in multiple b values.
Some more additions
Edited functions related to signal functions from base model to fix regressor function.
Edited all the functions in sparse_deconvolution.py.
Changed _flat_signal
Fixed matrix dimensions/arrangements of model_params.
Edited fit and predict functions.
Changed model params and fit so that the outputs are interweaved.
Made the inputs to _calc_rotations more general.
Progress on predict and fit
Model_params and fit work - design matrix now transposed when taking dot product (rot_vecs by vertices).
Tests for multi_bvals through fit
Many changes.  Not so sure
Get arrays instead of lists for internal variables.