[manifest] Update README with the new spec name and WG (#415)

And just when we did this rename, I noticed some people started use the name "Web Manifest". Oh well... agreeing on the color of the bikeshed is hard. Perhaps being consistent helps though :-)

Personally I think the Web App Manifest name goes nicely along with the new Progressive Web App buzzword people are excited about (for a reason).
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/manifest/pull/415

-- Commit Summary --

  * Update README with the new spec name and WG.

-- File Changes --

    M README.md (8)

-- Patch Links --

https://github.com/w3c/manifest/pull/415.patch
https://github.com/w3c/manifest/pull/415.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/manifest/pull/415