Added simple Code of Conduct

Author: TheDan64

.github/CODE_OF_CONDUCT.md

@@ -0,0 +1,15 @@
+# Inkwell Code of Conduct
+
+*Note: This is not a legal document.*
+
+The Inkwell team is committed to the following rules:
+
+* Treat everyone fairly.
+* Be kind and respectful to others.
+* Judge technical problems and solutions, not people.
+* Use polite language.
+* In case of disagreement use arbitrage of position of authority and responsibility (eg. project owner).
+
+We expect others to follow these rules as well.
+
+<small>This COC is based on [dpc's](https://github.com/dpc/public/blob/master/COC.md).</small>