Add Unit (engine).
I'm not sure about how i add a direction to the vector position of the
unit (in the constructor).
Add a JUnitTest for the class Unit.
To run the test, you must import the jar of JUnit at your build path (a
simple click at the line of the error can make this i think). And select
"Run as", and "JUnit", by clicking on the file "UnitTest.java".