v0.2.0.3 - Difficulty level balancing, etc

Here's what's new in 0.2.0.3:

• Omni tool placement range is now limited
• Upgrade cost turns red if you don't have enough
• Added ability to repair turrets
• Tweaked turrets, enemies, and enemy waves to balance difficulty level
• Renamed "Days Survived" to "Waves Survived"
• Day/night automatically fast-forwards between enemy waves
• Added "Armor" and "Shield" labels on the armor and shield indicator on turrets
• Fixed an error that could cause a turret to stop targeting altogether
• Performance improvements