Remove most instances of float usage

[dxxb]

This PR is not intended for merging as-is. It could be but at a minimum the game needs to be tested and constants / computation may need to be re-tuned. With a bit more effort the last instances of float could be removed (and fixed point trigonometric function used).

Aside from freed up RAM and flash, the speed gain is likely large.

Before:

Program:   28562 bytes (87.2% Full)
(.text + .data + .bootloader)

Data:       1929 bytes (75.4% Full)
(.data + .bss + .noinit)

After (with logo enabled):

Program:   25092 bytes (76.6% Full)
(.text + .data + .bootloader)

Data:       1715 bytes (67.0% Full)
(.data + .bss + .noinit)