[VA] {test before code} I15 EnemyManagement

#15 added a EnemyManagement class; first test: set up enemies
[VA] {test after code} I15 EnemyManagement

#15 enemy management: enemies setup after code
[VA] {refactoring} I15 EnemyManagement

#15 improved test cases for enemy management
[VA] {test before code} I15 EnemyManagement

#15 added unit test for enemy movement
[VA] {test after code} I15 EnemyManagement

#15 enemy movement test, not functional.
[VA] {other} I15 added a few enemies

#15 added a few enemies to the map, not moving.