Add detailed documentation (or references to external sites) about the ctest and google test frameworks. Include how to run the tests and where the executables are located.

The current code doesn't allow any of the boundary conditions to change over time. In order to run more interesting simulations, we need to be able to provide users the ability to modify the boundary conditions over various time steps.

Most of the code to allow for this should already be there. However, we'll need to do a few things first:

• Create a good file format that makes it easy f