Improve target coverage for the reuse license checker.

misc
----
  o Copyright notice update from onf v1 to onf v1.1

makefiles/etc/utils.mk
----------------------
  o Function path-by-makefilepath-by-makefile():
    - Replace $(subst include.mk) with $(dir) so path construction becomes generic.
    - Added wrapper function genpath-makefiles() to improve call usability.

makefiles/lint/license/include.mk
makefiles/lint/license/reuse.mk
makefiles/lint/license/install.mk
---------------------------------
  o Added requirements.txt for reuse tool install (ability to vesion and freeze for release).
  o Define command var REUSE= so local devs can override.
  o Added banner-{enter,leave} for logfile visibility.

makefiles/lint/license/include.mk

makefiles/lint/license/help.mk
------------------------------
  o Document a few missing targets for 'make help' and 'make lint-reuse-help'.

[HOWTO: test]
-------------
% make sterile
% make venv                 # install virtualenv
% make lint-reuse-install

% make sterile
% make lint-reuse-version

% make sterile
% make lint-reuse

Change-Id: I91f4789981f3d3c5bc744d2db99374f9790e3b98
diff --git a/makefiles/lint/license/include.mk b/makefiles/lint/license/include.mk
index b8f70f4..2f8e497 100644
--- a/makefiles/lint/license/include.mk
+++ b/makefiles/lint/license/include.mk
@@ -15,6 +15,11 @@
 # limitations under the License.
 # -----------------------------------------------------------------------
 
+##-------------------##
+##---]  GLOBALS  [---##
+##-------------------##
+REUSE ?= $(venv-activate-bin)/reuse
+
 ##--------------------##
 ##---]  INCLUDES  [---##
 ##--------------------##
@@ -23,7 +28,7 @@
 include $(ONF_MAKEDIR)/lint/license/reuse.mk
 
 # Alias targets
-lint-license : lint-reuse
+lint-license     : lint-reuse
 lint-license-all : lint-reuse-all
 lint-license-mod : lint-reuse-mod
 lint-license-src : lint-reuse-src