Introduce CSP headers to Kalamar (start of #72)

Change-Id: I84b7ff0accab3d783ad653fae123c25fee1d92b9
diff --git a/Changes b/Changes
index 74f8ed6..947d6d6 100755
--- a/Changes
+++ b/Changes
@@ -1,5 +1,6 @@
 0.41 2021-01-14
         - Introduce CORS headers to the proxy.
+        - Introduce Content Security Policy.
 
 0.40 2020-12-17
         - Modernize ES and fix in-loops.