Create NOTICE file for CNCF donation compliance

Added a NOTICE file to comply with CNCF donation rules.

Author: aojea

NOTICE

@@ -0,0 +1,13 @@
+When donating the kindnet project to the CNCF, not all contributors were reached
+to sign the CNCF CLA prior to donation. As such, according to the CNCF rules to donate a repository,
+we must add a NOTICE referencing section 7 of the CLA with a list of developers who could not be reached.
+
+`7. Should You wish to submit work that is not Your original creation, You may
+submit it to the Foundation separately from any Contribution, identifying the
+complete details of its source and of any license or other restriction
+(including, but not limited to, related patents, trademarks, and license
+agreements) of which you are personally aware, and conspicuously marking the
+work as "Submitted on behalf of a third-party: [named here]".`
+
+Submitted on behalf of a third-party: @mhines01
+Submitted on behalf of a third-party: @zx-zx