Requirements manager integration

Mark, Sam and I have merged the requirements manager that was developed by the software engineering class last D-Term, at the request of Prof. Pollice. We kept the commit history of team 2's repository and made the changes requested from the last pull request. We moved the Java target version to the build-common.xml file, and switched to Java 1.7 because the RequirementsManager uses generics that were introduced in Java 1.7.

Thanks,
Nathan, Mark and Sam