21-049 OAB issues

[cmheazel]

Issue 1: Change Implementation Specification to Implementation Standard once we confirm that Implementation Standard is a valid OGC document type.
Issue 2: What is the appropriate level of detail for a conceptual Model? Consider dropping requirements and conformance testing for ISO 19103 types.
Issue 3: Section 6.1.2 - "lines" is in lower case. Make upper case like others
Issue 4: Section 6.2.2 - Feature with Lifespan requirement is blank in PDF. This appears to be a column width issue.
Issue 5: Requirement 21 - change requirement name from "poi-link" to "link"

[cmheazel]

Issues 3 and 5 were fixed on March 19.
Issue 4 appears to have been fixed by an update to Metanorma. Waiting on GitHub CRON run to verify.