Updated Visualization for single lens.  Changes:
- Updated to use new mainWFS.py which has the lenslet array for the numerical solution
- Improved plot aesthetics
- Removed SingleLens.py which is no longer needed
- Attempted to improve readability and modularity
Added calculation and plot of error between numerical and analytical intensity distributions.  Removed random wavefront generation for just a planar wavefront input.
Added Noise parameters to paramsSensor to work with new master paramsSensor
Merge pull request #84 from faitdivers/WFS_iss58

Updated visualization for single lens.