Dev/contributing (#144)

* start a contributing guide for automation-tools.

* forgot to add the URL

* linting

Author: eviau-artefactual

CONTRIBUTING.md

@@ -0,0 +1,10 @@
+# Contributing to automation-tools
+
+Thank you for your interest in making a contribution to automation-tools.
+
+Since this project is used mostly in the general context of Archivematica, we
+invite you to read the [Archivematica contributing guide](https://github.com/artefactual/archivematica/blob/qa/1.x/CONTRIBUTING.md)
+ to learn how to contribute to automation-tools.
+
+Any information specific to the automation-tools project should be listed
+below.