RF Cavity is not accelerating/decelerating.

[William Shields]

An example file is attached. The lattice consists of a strong angled dipole after the cavity to act as a spectrometer but the particles continue on a reference trajectory through the magnet. Generating Root output and inspecting the samplers shows no change in energy after the cavity.

[William Shields]

Fixed - incorrect magnet strength key. Updated class to exit upon incorrect key to prevent further such errors.