Virtual Member Functions and Exceptions

[blakemulnix]

This pull requests adds virtual member functions and the tests and documentation for that feature.

This pull request also adds exceptions and the tests for that feature. The documentation for exception still needs to be completed.

[blakemulnix]

I added documentation for exceptions and I updated the documentation for maps to include all maps functions.

[ryanmrichard]

It just occurred to me that we need a way to register an exception handler which can handle any exception (the equivalent of C++'s catch(...){ /* handler code */ };