Adding missing period

README.md

@@ -205,7 +205,7 @@ Contributing
 
 To contribute to this open source project please review the [Mattermost Contribution Guidelines]( http://www.mattermost.org/contribute-to-mattermost/).
 
-To setup your machine for development of mattermost see: [Developer Machine Setup](scripts/README_DEV.md)
+To setup your machine for development of mattermost see: [Developer Machine Setup](scripts/README_DEV.md).
 
 License
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