Fix a typo in README (#944)

Author: liamtoney

README.rst

@@ -132,7 +132,7 @@ contribute. What could you possibly offer?
 We assure you that the little voice in your head is wrong.
 
 **Being a contributor doesn't just mean writing code**.
-Equality important contributions include: writing or proof-reading documentation,
+Equally important contributions include: writing or proof-reading documentation,
 suggesting or implementing tests, or even giving feedback about the project (including
 giving feedback about the contribution process). If you're coming to the project with
 fresh eyes, you might see the errors and assumptions that seasoned contributors have