Created Presentation.md

Created a Presentation.md file and added instructions for installing both Trinity and Oases on a fresh Ubuntu system.
Rewrite

The installation and configuration become much more complicated than I'd remembered it being, so I pretty much rewrote the entire page to condense the instructions.
Modified the R analysis section

Installing R 3.0 on Ubuntu 12.04 was more annoying than I'd anticipated, and complained when it found a number of packages that had been built using R 2.x.
Created a brief description of what I intend to present
Finally added scripts used to run the assemblers
Merge branch 'master' of https://github.com/umd-byob/presentations
Merge pull request #4 from trgibbons/master

Ted's presentation.