First modifications to the pseudospectral lab.
Major changes to the first pseudospectral lab. Added some code vectorizing the construction of the differentiation matrix. Added some code solving the nonlinear boundary value problem resulting from the use of the calculus of variations to minimize the area of a surface of revolution.
Modified first pseudospectral lab.
Work on second pseudospectral lab.
Work on second pseudospectral lab.
Beginning plotting.py file for the River Crossing problem.
Updates to RiverCrossing Lab.
Added derivation of the functional for the River Crossing lab.
Some preliminary modifications made to the Poisson2d lab, the RiverCrossing lab, and the pseudospectral lab in preparation for the 1st run of Vol4, semester 2.
Split up the Poisson lab into an introductory finite difference method lab, and a Poisson2d lab. Cleaned up the finite difference lab, and the first pseudospectral lab.
Deleted a backup copy of the old version of the pseudospectral lab.
Added a graph to the Rivercrossing lab and made some minor edits.
Modified all the plot graphics so they were not subplots in plots.py.
Had to rename MelScale.pdf
Add introductory section to the Finite Difference Lab.
Adding revisions to the pseudospectral lab and the rivercrossing lab to the repository.
Merge branch 'develop' into ps_revisions

Conflicts:
	Applications/Poisson/Poisson.tex
	command.tex
Added a math operator to command.tex
Added example_convergence.pdf to Finite Difference Method lab.
Added figure2.pdf to Finite Difference Method Lab.
Added figure3.pdf to Finite Difference Method Lab.