Silence UserWarning: Size of toroidal domain...

[johnomotani]

From @ZedThree on Slack:
Is there a way to silence this warning: "UserWarning: Size of toroidal domain as calculated from nzdz (76.8 is not the same as 2pi(ZMAX - ZMIN) (6.283185307179586): using value from dz"?

[johnomotani]

There isn't. Looking at it again, maybe we should remove the warning and trust BOUT++ that if ZMAX was set by the user then dz=2pi(ZMAX-ZMIN)/nz. If I remember right, I added the test when I put in dz instead of always using ZMAX (to support more general cases) as a sanity check. The only time when it might possibly be useful is if someone set all of ZMIN, ZMAX and dz but only set dz by mistake (copying a BOUT.inp from someone else maybe). I'd lean towards removing the warning - it's probably much more common to run when setting dz on purpose (when this warning is just annoying) than to make the particular mistake that it highlights and never notice. It's probably something BOUT++ should check rather than xBOUT, although if all options were written to output and we could check whether an option was set by defaults or by the user then we could make a better version of the check.