Makefile library merge with onf-make and voltha-lib-go

makefiles/
----------
  o Import standalone makefile directories to checkin smaller parts of a mega patch.
  o Build out directory hierarchy by topic and feature.

makefiles/lint/yaml/
--------------------
  o Pull in logic evolved in repo:voltha-lib-go.
  o Refactoring: support special snowflake targets by repository.
  o ci-management and voltha-lib-go use distinct yamllint.conf files.
  o Separate until there is time to review and consolidate.
  o Added deps for on-demand local install of yamllint.
    - requirements.txt could be used but every build would incur overhead.

Makefile
--------
  o Use latest syntax from repo:onf-make.
  o No need to set path variables, makefiles/include.mk can infer them.
  o Added a help target to explicitly display targets and suggestions.
  o Logic is bundled in libraries and use of 'make help' is not well known.

Change-Id: Id8eba6f914a7bfe9a31637901bd8fb78a387e0c2
diff --git a/makefiles/lint/yaml/byrepo/voltha-lib-go/urls b/makefiles/lint/yaml/byrepo/voltha-lib-go/urls
new file mode 100644
index 0000000..8747658
--- /dev/null
+++ b/makefiles/lint/yaml/byrepo/voltha-lib-go/urls
@@ -0,0 +1,5 @@
+# -*- makefile -*-
+
+https://yamllint.readthedocs.io/en/stable/configuration.html
+
+# [EOF]
\ No newline at end of file