Let RegularSurface.compare_topology() allow a precision level

[jcrivenaes]

With regards to:

xtgeo/src/xtgeo/surface/regular_surface.py

Line 1422 in f208649

def compare_topology(self, other, strict=True):

The comparison of e.g. xori, yori requires now an exact match. However, there may be numerical differences, or it may be that the user
requires a more lose match for some reasons.

The proposal is to add an absolute tolerance, like

def compare_topology(self, other, strict=True, abs=0.1)

In this case, abs=0.01 will mean that an xori value of 450000 will allow a range 449999.09 to 450000.1

Possibly also consider a relative tolerance.