Updates made to heat flow lab.
Merge branch 'develop' into heat_flow

Merge with develop
Clarification of problem 2/minor edits
Modified first two finite difference labs.
Clarification/reminders to see documentation
Merge branch 'develop' of https://github.com/byuimpactrevisions/numerical_computing into develop
Beginning update of Hysteresis lab.
Further modifications to the Hysteresis lab.
Edited matplotlib section of lab. Started mayavi section.
Created plots for students to compare work.
Created .py files to be input into lab.
Further modifications to Hysteresis lab.
Added several graphs to heat flow lab.
Minor change here.
Merge branch 'develop' into heat_flow

Merging with develop
Merge pull request #605 from joshualy/heat_flow

Heat flow
Merged givens with LS
Merge pull request #12 from byuimpactrevisions/given

Merged givens with LS
Additions to Hysteresis lab.
Merge branch 'develop' into hysteresis

Merge into develop.
Beginnings of the Lorenz equations and chaos lab.
Added some basic exposition on the Lorenz equations.
Also added a few examples of how to use animation in Mayavi.
wrote mayavi section and problem, updated solutions