[charter-html] Update data about Web Annotation joint deliverable (#93)

This PR updates the information about the joint deliverable (Robust Anchoring) with the Web Annotation WG and adds that WG to list of liaisons. 

(WebAnnotWG has not yet published a TR for this deliverable, although the have started work on "RangeFinder API"; see <https://www.w3.org/annotation/wiki/PubStatus>).
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/charter-html/pull/93

-- Commit Summary --

  * Update data about Web Annotation joint deliverable

-- File Changes --

    M group-charter.html (7)

-- Patch Links --

https://github.com/w3c/charter-html/pull/93.patch
https://github.com/w3c/charter-html/pull/93.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/charter-html/pull/93