Fix example SingleParticleRadiationWithLaser to work in 2D

This branch fixes the following issues:
 - It sets the frequency range correcly. (Previously it was 2 orders of magnitude too low.)
 - It places the electron in the simulation box. (Previously, the electron was initialize outside of the box and was never simulated.)
 - It draws the laser in the png output. (Prevously, no laser was drawn.)
 - It rewrites the setup to work in 2D.
 - It adds a compile test to check whether radiation works in 2D. 
Do we have BETA0_Z in the 2D case?