RFR: Update README.md

[Joe Darcy via github.com]

Fix typo in description of hgbridge.

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Commits:
 - ebd737b8:	Update README.md
			Fix typo in description of hgbridge.

Pull request:
http://git.openjdk.java.net/skara/pull/33

Webrev:
https://openjdk.github.io/cr/skara/33/webrev.00

Patch:
http://git.openjdk.java.net/skara/pull/33.diff

Fetch command:
git fetch https://github.com/openjdk/skara.git pull/33/head:pull/33