Typo correction

CONTRIBUTING.md

@@ -27,7 +27,7 @@ If you'd like to submit a pull request please adhere to the following:
 6. *Do not* use Ruby 1.9 hash syntax
 7. *Do not* use Ruby 1.9 stubby proc syntax
 
-Plase note that you must adhere to each of the above mentioned rules.
+Please note that you must adhere to each of the above mentioned rules.
 Failure to do so will result in an immediate closing of the pull
 request. If you update and rebase the pull request to follow the
 guidelines your pull request will be re-opened and considered for