Added link to How to Work on a PR Efficiently
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+Please fill in some details about the PR, below.
+If the PR contains source code please make sure to run Checkstyle on it first.
+If you add unit tests we'll love you forever!
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+You might also want to read "How to Work on a PR Efficiently":
+https://github.com/MovingBlocks/Terasology/wiki/How-to-Work-on-a-PR-Efficiently
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### Contains
