Add method to DataManager to retrieve data for a Player instance.
Add methods to check and correct yaw and pitch to LocUtil.
Add Methods to correct yaw and pitch to MCAccess.

An implementation for NCPCompatBukkit is missing.

Note that the native access can not set lastYaw nor lastPitch in
PlayerConnection (private), but it could set lastYaw and lastPitch in
EntityPlayer.

Can't guarantee this actually helps with stuff like derp/magnet, because
we can not really set the outcome of a PlayerMoveEvent without
rubberbanding the whole planet. Hacks could send enough packets per tick
to keep freezing people - we might be able to keep track of yaw/pitch
correction and cancel (most) attacking for the same tick after yaw
correction (invalidate "same" with in-bounds yaw).
Make use of yaw/pitch correction (silent correction).