Floating Health Bar for Enemy Planes / Buildings

[karastoyanov]

[rayapetkova]

• Made a class for rects with floating-point parameters. We needed this because the x and y of the images are floating-point numbers while moving but the rects in pygame work with only integers. --> 128bebc

[TamerAnefiev]

Enemies now have sticky healthbars on top of them. Healthbar and armorBar is dynamically centered.
Tested if the healthbar will result in bad position when the plane hits both left and right walls.