Black Hole Invasion!

Welcome to Black Hole Invasion! Here are the modifications that were made to the game:

1. Created three unique levels with different challenges
2. Created logical progression between levels that tell a story of fighting off enemies invading through black holes
3. Added in story text to each level 
4. Added new script called TextTimer.cs for timing out the story text from the screen
5. Wrote and added in custom background music for all the levels (though the main menu music is the same as the tutorial)
6. Created three types of boss enemies for the final level:
   1. Boss version of straight shooter chaser (larger size, larger projectiles, faster projectiles)
   2. Boss version of diagonal shooter chaser (larger size, larger projectiles, faster projectiles)
   3. Boss version fo standard shooter chaser (larger size, larger projectiles, faster projectiles)