Renumber metrology needs section following the merge of sections B, C, E

[ftessier]

This implements the suggestion in issue #35.

[millemm]

Maybe we should discuss with executive committee? It seems the lettering was kept to preserve the history of the subcommittee name changes. Although, not clear to me how important this really is. It certainly would clean up the document if we started fresh with the lettering.

[ftessier]

@millemm Yes the idea is to discuss with the committee! But you are the only one here 😄 I wanted to give you a taste of how the change review process goes (a proposed change is called a pull request on github). You can ask for specific reviewers reviewers (as I did with you), you can assign people, etc. The idea would be that a change would be merged in the main branch once everyone approves it.

About the change itself, I am strongly in favour of updating the numbering, and the legacy version numbering can be explained in the text, similar to the intro in section B. At some point it is necessary to disambiguate the B,C,E. That point is now.