All trigonometric functions and vector classes assume North-West-Up axes
convention, so using North-East-Down convention with them is really
error-prone. We've broken something every time we touched the drive
classes.
We originally used North-East-Down to match the joystick convention, but
the volume of long-lived bugs has made this not worth it in retrospect.
The rest of WPILib also uses North-West-Up, so this makes things
consistent.
KilloughDrive was removed since no one uses it.
If xSpeed == -0.0 and zRotation > 0, the algorithm assumes it's in the
third quadrant instead of the first since +0.0 == -0.0.
Also added tests for inverse kinematic functions, fixed some
MecanumDrive test bugs, and added Java MecanumDrive.driveCartesianIK()
and KilloughDrive.driveCartesianIK() overloads with defaulted gyro angle
that C++ already had.
Fixes#4022.
