Made changes to Lab 5 in volume 1 (complexity and sparse matrices).
Merge pull request #318 from abefrandsen/develop

Made changes to Lab 5 in volume 1 (complexity and sparse matrices).
Regenerated plots for nearest neighbor lab.
Also reformatted solutions/plot generation file.
Merge pull request #320 from insertinterestingnamehere/plot_regen

Regenerated plots for nearest neighbor lab.