Misc library edits and cleanup

Makefile
--------
  o Simplify initial bootstrap path construction logic used to load
    the top level library makefile repo:onf-lib/makefiles/include.mk.
  o Remove direct includes (consts.mk) that are loaded by include.mk.

bin/setup.sh
------------
  o Update repo:onf-lib installer script.
  o Re-arrange inlined logic into functions.
  o Added a banner message to display installation progress.
  o Added install_config_mk(), relocate sandbox/config.mk into sandbox/makefiles/onf-lib/config.mk.
  o Added detection logic to handle patching python to v3.10+.

makefiles/etc/include.mk
------------------------
  o Remove dup logic, include.mk mirrored features.mk, changed to simply include features.mk.

makefiles/include.mk
--------------------
  o Relocate display of include/display of help target trailer message
    from top level Makefile into the library makefile hierarchy.

makefiles_include_mk.ex
-----------------------
  o Added git-submodule maintenance helper targets & dependencies that
    consuming repository makefiles can use to automate submodule checkout
    from a clean state.

Change-Id: Id8df17cef09a17325137934d04e58d87ea370621
diff --git a/makefiles/git/detect-local-edits.mk b/makefiles/git/detect-local-edits.mk
new file mode 100644
index 0000000..d0afc84
--- /dev/null
+++ b/makefiles/git/detect-local-edits.mk
@@ -0,0 +1,23 @@
+# -*- makefile -*-
+## -----------------------------------------------------------------------
+## Intent: Targets in this makefile will determine if locally modified
+##   files exist in the sandbox.  VOLTHA currently uses this logic to
+##   detect when go {tidy, update} have indirectly modified vendor go.mod
+##   files during a build or test.
+## -----------------------------------------------------------------------
+
+$(error DISABLED -- not yet deployed/in use)
+
+# $(MAKE) --no-print-directory detect-local-edits
+
+## ---------------------------------------------------------------------
+## Intent: Determine if sandbox contains locally modified files
+## ---------------------------------------------------------------------
+clean-tree := git status --porcelain
+detect-local-edits:
+	$(HIDE)[[ `$(clean-tree)` == "" ]] || {\
+  echo "ERROR: Untracked files detected, commit or remove to continue" \
+  && echo "`git status`" \
+  && exit 1; }
+
+# [EOF]