Limit of core_shell_cylinder should be exactly the same as hollow_cylinder

[butler]

Checking with 4.2, the core_shell_cylinder using an SLD of 6.34 for both the core and solvent and otherwise the same structural parameters SHOULD give the exact same result as the hollow_cylinder using a solvent SLD of 6.34. It is "close" but not the same. In particular the Intensity at q=1E-3 is about 15% different and the oscillations a just a tad off.
the parameters used were:

R_in = 30
R_out = 10
L = 400
background = 0.001
Vol Frac of TOTAL cylinder = 0.05

Not sure if this is just a numerical thing but seems a bit much for that? This needs investigating and possibly fixing