Unit tests are easier to write.

Unit tests should be relatively easy to write now.

1. Add a test: ```libra/test/tests/Test*.cpp```
2. Add the required libra objects into the ```USER_OBJ``` list in ```libra/test/Makefile```
3. The make file should automatically build and link against anything that you've specified.

Notes:
* Unit tests won't run unless Libra builds completely