PLUS : Projectiles rotate towards target
PLUS : Buildings invisible before level start

* on level start, each building rederer's enabled boolean is set to
false, and when pressing the Start level button, each building's
renderer's enabled boolean is set to true
PLUS : Removing Destroyed Rocks from Wave List

* The wave list from MakeWave script
* The start of the level button description changed from"Start Wave" to
"Start Level"
PLUS : Rocks that leave the atmosphere will be destroyed in 2.5 seconds
BUG FIX : Issues with Destroying rocks

Now, instead of calling Destroy(rock), you call
rock.GetComponent<HandleRock>().destroyStuff(), which also removes
healthbar-related gameObjects
PLUS : Making levels for the game

The values change depending on the name of the scene, inside the level
script
PLUS : Properly reworked level making

Now based on the level you are at, certain buildings are unlocked.