Added new upgrades: "Headhunter", "Damage Statistics" and "Power Shot"

Reworked battle result screen with more details

Added amount of enemies to level selection and also added a few icons there

Orc move speed is now increasing per level

Added icons for most upgrades

Upgrade tooltips now show total values

Increased base fire duration and tick rate of flamethrower so that orcs get at least 1 time fire damage even from an non-upgraded flamethrower

Decreased fire tick damage to balance the flamethrowers

Fixed that multiple strafing runs could be called at the same time via the pause menu

Added stat panels for abilities

Moved explosion simulation and rendering to GPU which should improve performance

Improved performance of big explosions

Fixed orcs and shadows having an offset when resizing the window

Various smaller fixes and performance improvements