Provide an extension for validating section IDs #81
Description
We want our section IDs to follow a predictable structure and for that structure to be enforced. The IDs of top-level sections should be in kebab-case. The IDs of child sections should being with their parent's ID followed by . and then followed by kebab-case. The following are all valid:
top-leveltop-level.nested-childtop-level.nested-child.grandchild