Auto merge of #740 - glennw:rev-update, r=larsbergstrom
Auto merge of #740 - glennw:rev-update, r=larsbergstrom

Add Gankro to WR reviewers list.

Some reviews in WR that Gankro has worked on:

https://github.com/servo/webrender/pull/1830
https://github.com/servo/webrender/pull/1799
https://github.com/servo/webrender/pull/1834
https://github.com/servo/webrender/pull/1664

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This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/saltfs/740)
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servo/saltfs,servo/saltfs