Merge branch 'master' into 'master'

getting_started/04_numpy.ipynb

getting_started/04_numpy.md

getting_started/04_numpy/.solutions/calc_column_mean.py

getting_started/04_numpy/.solutions/concat_affines.py

getting_started/04_numpy/04_numpy.ipynb

getting_started/04_numpy/2d_array.txt

getting_started/04_numpy/comma_separated.txt

getting_started/04_numpy/space_separated.txt

getting_started/04_numpy/xfms/subj1/example_func2highres.mat

getting_started/04_numpy/xfms/subj1/highres2standard.mat

getting_started/04_numpy/xfms/subj2/example_func2highres.mat

getting_started/04_numpy/xfms/subj2/highres2standard.mat