Change the writeable flag back to its original state when finished.
Test a more flexible approach allowing list of mixed dtypes.
Comparison of three version of functions length and set_number_of_points in Cython.
Make a new benchmarking function to compare Orignal, MrBago and the flexible version of functions length and set_number_of_points in Cython
Update benchmarking function
Improved flexible version
Made test_streamline Python3 compatible
Merge pull request #431 from MarcCote/fix_streamlinespeed

Change the writeable flag back to its original state when finished.