me fix
Add concept of class sessions
Merge interface changes from github/patch-1

Conflicts:
	src/com/jakobcornell/compsci/schoolorganizer/Class.java
	src/com/jakobcornell/compsci/schoolorganizer/EnrollmentException.java
	src/com/jakobcornell/compsci/schoolorganizer/IClass.java
	src/com/jakobcornell/compsci/schoolorganizer/IStudent.java
	src/com/jakobcornell/compsci/schoolorganizer/IStudentBody.java
	src/com/jakobcornell/compsci/schoolorganizer/Student.java
	src/com/jakobcornell/compsci/schoolorganizer/StudentBody.java
implement class sessions
fix imports