version 3.0.0

Now supports different acceleration and deceleration rates! (to support different deceleration rates, some methods, including the constructor had to be changed in non backwards compatible ways, so this release starts a new major version.

Also now supports velocity control and setting a velocity target! see: setVelTarget() and setVelConstant()

As this version has a completely rewritten formula for calculating movement, please test it thoroughly before trusting it, and please let me know if you find any issues.