[img-conversion] Convert to spec (#14)

FOR REVIEW ONLY. DONT MERGE THIS! 

I've started reworking the spec to include algorithms, etc. I've also moved to using contiguous WebIDL, as the current spec uses the deprecated inline webidl. 
You can view, comment on, or merge this pull request online at:

  https://github.com/WICG/img-conversion/pull/14

-- Commit Summary --

  * Added tidy config file
  * Started reworking spec

-- File Changes --

    A .tidyrc (4)
    M index.html (381)

-- Patch Links --

https://github.com/WICG/img-conversion/pull/14.patch
https://github.com/WICG/img-conversion/pull/14.diff

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/img-conversion/pull/14