Add CODEOWNERS

We'll likely want more specific ownership, e.g. for the Data Platform team's playbooks.
These can be added as refining rules under the default, as they override rules
higher in the file rather than adding to them.

Author: spikeheap

.github/CODEOWNERS

@@ -0,0 +1,7 @@
+# The default owners for are the Hackney development team, and more specialised 
+# ownership can be added to directories/folders as needed.
+#
+# Note that order matters: more specific rules lower in this file will override 
+# the default, NOT add to it
+
+*       @LBHackney-IT/development-team