Semver leading zeros now rejected in flag evaluation

Patch changes

• be9b78b Reject semver values with leading zeros in local flag evaluation. Per semver 2.0.0 §2, numeric identifiers must not include leading zeros — values like 1.07.3 are not valid semver and should not match targeting conditions. Both override values and flag values are now validated; invalid inputs raise InconclusiveMatchError so the condition does not match. — Thanks @dmarticus!