[VOL-5194] - Refactor and use repo:onf-make as a git-submodule

Makefile
--------
  o Added target view for interactive rendering of README.md
  o Use printf VS echo in target help to normalize formatting

README.md
docs/todo.md
docs/VARIABLES.md
-----------------
  o Begin documenting makefile variables and features for library makefiles.

Change-Id: If75417c45363ee5c6a514fe9ebd4414ba8cf0cf7
diff --git a/Makefile b/Makefile
index d830da6..96b8f26 100644
--- a/Makefile
+++ b/Makefile
@@ -32,4 +32,23 @@
 ## Display make help text late
 include $(ONF_MAKEDIR)/help/trailer.mk
 
+## -----------------------------------------------------------------------
+## Intent: Helper target for interactive README.md viewing
+##   Note: This target has limited use for repo:onf-make and this directory
+##   Todo: Add makefiles/[lint/]md/include.mk and generalize logic
+## -----------------------------------------------------------------------
+view-docs-src := README.md $(wildcard docs/*.md)
+view-docs-dep := $(addprefix view-dep^,$(view-docs-src))
+
+.PHONY: view $(view-docs-dep)
+view :: $(view-docs-dep)
+
+$(view-docs-dep): # view-dep^README.md => README.md
+	-pandoc $(lastword $(subst ^,$(space),$@)) | lynx -stdin
+
+help ::
+	@echo
+	@printf '  %-25.25s  %s\n' 'view'\
+  'Rendering *.md docs for interactive viewing'
+
 # [EOF]
diff --git a/README.md b/README.md
index 48b1916..b10b43d 100644
--- a/README.md
+++ b/README.md
@@ -53,19 +53,6 @@
     |   |   |   |-- shell.mk        Invoke shellcheck command on scripts
     |   |   |   |-- yaml            Syntax check yaml configs
   
-TODO
-====
-
-- Refactor and merge logic from available repository makefiles/ directories.
-- Update to make use of library makefiles
-
-    - [setup.sh](http://github.com/opencord/onf-make/blob/master/bin/setup.sh)
-    - {repository}/makefiles/{local, onf-make}/
-    - Create [config.mk](https://github.com/opencord/onf-make/blob/master/config.mk) to enable targets and features.
-
-- Exercise make lint targets, bulk cleanup is needed across all repositories.
-- Relocate $sandbox/config.mk into makefiles/config.mk
-
 NOTES
 =====
 
@@ -76,3 +63,10 @@
 - README.md can be rendered locally using
 
     - pandoc README.md | lynx -stdin
+    - make view
+
+SEE ALSO
+========
+
+- [Makefile Variables & Debugging](docs/VARIABLES.md)
+- [Todo List](docs/todo.md)
diff --git a/docs/VARIABLES.md b/docs/VARIABLES.md
new file mode 100644
index 0000000..0c495c8
--- /dev/null
+++ b/docs/VARIABLES.md
@@ -0,0 +1,43 @@
+make macros
+-----------
+
+Sandbox directories
+===================
+
+| Varname     | Description                                               |
+| ---         | ---                                                       |
+| ONF_MAKEDIR | Path to library repo:onf-make/makefiles/ directory        |
+| MAKEDIR     | Path to per-repository, local makefiles/ directory.       |
+|             |                                                           |
+| onf-mk-top  | Path to top level sandbox directory (contains makefiles/) |
+| onf-mk-lib  | Path to library repo:onf-make/makefiles/ directory        |
+| onf-mk-loc  | Path to per-repository, local makefiles/ directory.       |
+| onf-mk-tmp  | Threaded makefile scratch area (cleanup behind yourself!) |
+
+Runtime modes
+=============
+
+| Varname | Description                                               |
+| ---     | ---                                                       |
+| DEBUG   | Enable makefile debugging, display includes while loading |
+| VERBOSE | |
+
+Lint Conditionals
+=================
+
+| Varname          | Tool     | Description                                  |
+| ---              | ---      | ---                                          |
+| NO-LINT-DOC8     | text     | Disable reStructured text syntax checking    |
+| NO-LINT-FLAKE8   | python   | Disable tool:flake8 syntax checking          |
+| NO-LINT-GOLANG   | golang   | Disable tool:gofmt syntax checking           |
+| NO-LINT-GROOVY   | groovy   | Disable tool:groovy syntax checking          |
+| NO-LINT-JJB      |          | Disable Jenkins Job Builder (JJB) syntax checking |
+| NO-LINT-JSON     | json     | Disable config file syntax checking          |
+| NO-LINT-MAKEFILE | makefile | Disable tool:make --dryrun, --no-undef syntax checking |
+| NO-LINT-PYLINT   | python   | Disable tool:pylint syntax checking          |
+| NO-LINT-PYTHON   | python   | Disable all python syntax checking           |
+| NO-LINT-REUSE    |          | Disable license checking                     |
+| NO-LINT-ROBOT    |          | Syntax check tool:robot test framework       |
+| NO-LINT-SHELL    | bash     | Run tool:shellcheck on script sources.       |
+| NO-LINT-TOX      |          | Syntax check virtualenv test automation      |
+| NO-LINT-YAML     | yaml     | Disable config file syntax checking          |
diff --git a/docs/todo.md b/docs/todo.md
new file mode 100644
index 0000000..8c40dc3
--- /dev/null
+++ b/docs/todo.md
@@ -0,0 +1,12 @@
+TODO
+====
+
+- Refactor and merge logic from available repository makefiles/ directories.
+- Update to make use of library makefiles
+
+    - [setup.sh](http://github.com/opencord/onf-make/blob/master/bin/setup.sh)
+    - {repository}/makefiles/{local, onf-make}/
+    - Create [config.mk](https://github.com/opencord/onf-make/blob/master/config.mk) to enable targets and features.
+
+- Exercise make lint targets, bulk cleanup is needed across all repositories.
+- Relocate $sandbox/config.mk into makefiles/config.mk