Adding acknowledgement for Zack (#402)

Adding acknowledgement for Zack‘s contribution to the pattern. 
Also aligning formatting of KIs.

Author: spier

patterns/2-structured/document-your-guiding-principles.md

@@ -173,8 +173,13 @@ A typical engagement model at GitHub looks like this:
 
 ### Robert Bosch GmbH
 
+#### Purpose
+
 Fostering collaboration, learning and innovation is the main focus of the Bosch InnerSource initiative (BIOS).
-To that end, they applied the following principles:
+
+#### Principles
+
+To that end, Bosch applied the following principles:
 
 - **Openness**: We lower the barriers for entry into BIOS communities as much as we can.
 - **Transparency**: We are radically transparent and share our work products, our communication, and our decision making with all associates in the company.
@@ -197,6 +202,10 @@ Structured
 * Isabel Drost-Fromm
 * Georg Grütter
 
+## Acknowledgements
+
+* Zack Koppert - for sharing GitHub's approach in the Known Intances
+
 ## Alias
 
 Explicit InnerSource Principles