Chapters 1-3 and Algorithms Appendix converted to MathBook XML

The first three chapters of Applied Discrete Structures have been converted to MathBook XML.  There will be some adjustments to be made (like adding solutions to many of the exercises) but these chapters are in pretty good shape.

At the request of Rob Krueger (Concordia U.), I've also updated and converted the short appendix on Algorithms that we had in the 1989 edition. I added a section on the Invariant Relation Theorem that I've been meaning to write up for a while.  Having the ability to include Sage Cells into the text really enhances the html version.

The html version is available at  http://faculty.uml.edu/klevasseur/ads2

After finals and a few other chair related tasks (64 days left as I type this!), I'll make a LaTex version available.