More updates on the DWBP document

Hi Annette,

We made more updates on the document to address the following comments[1].
Please, take a look and tell me if it's ok.

79 (machine-readable data format)
https://github.com/w3c/dwbp/commit/b85fa424e9c0ca1f7c795a7f367652279e36ecfc

61 (document API)
https://github.com/w3c/dwbp/commit/5879a077989310a409145bf476af57ff0a121342

27 (context diagram)
https://github.com/w3c/dwbp/commit/9e6ad2afea3379cc4bde17ba833cf4c00c680b61

82 (data access introduction)
https://github.com/w3c/dwbp/pull/387/commits/b3c0bb30ffa66a5afc20e5d2aaa5ef9b756d1439

87 (challenges diagram)
https://github.com/w3c/dwbp/commit/1aa0c50ab36b085006337ecc0629dafbab8b0d41

Thanks!
Berna

[1]
https://www.w3.org/2013/dwbp/wiki/Comments_to_be_considered_in_the_last_call_working_draft

-- 
Bernadette Farias Lóscio
Centro de Informática
Universidade Federal de Pernambuco - UFPE, Brazil
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