CRA-538, CRA-661: Removed a constructor in blockedlogscommon. Fixed a bug in reading wells.
CRA-531: Fixed bug with CutWell() where top_surf.GetZ(x,y) returned missing.
CRA-553, CRA-557, CRA-568: Fixed a bug with eroded surfaces in simbox for multiinterval, and with GenerateMultiIntervalBackground.
CRA-505, CRA-596: cleanup.