Sentinels of the Void V0.4

There are 2 new towers, 2 new maps, 10 new waves, 2 new enemies, and a new boss.

To make things go quicker, the "next wave" button, has a double purpose as a double speed button.

Each enemy has a health bar indicating how much health they've lost.

The map selection screen now shows a preview of the map on each button.

Since there are more maps, there is also the ability to go between pages of maps.

Towers also now have another upgrade path, each with 2 upgrades. All towers also have sprites. These sprites also face the direction that they've shot.