New check for named instance consistency

[davelab6]

In Roboto Flex, the width axis max is 151, but there's a MSOT axis registry and GF axis registry named value of 150. I'd like to propose a check that, if any FVAR axis min/def/max or STAT named instance location is within say 10 units of a registry named value, we WARN, and if its off by 1 or 2, we FAIL; this is to encourage consistency between instances people use by wanging a slider to min/max, using a STAT table named instance, and using a registry named instance.