VOL-4836 - Source edits to trigger a jenkins job.

Makefile
--------
  o Add copyright notice and common variables/includes.
  o Added a conditional variable to support local golang use w/o docker.
  o Replace variable decoration ${GO} with $(GO) -- vars are make not shell.
  o Added makefile target sterile to remove the golang module cache.

internal/pkg/commands/log.go
----------------------------
  o Fix content problem reported by gofmt -d.

makefiles/
----------
  o Added LOCAL_LINT=1 to support source linting outside of docker.
  o Also copy in linting libraries to check licenses, shell, yaml, etc.
  o Added todo.mk to document 'go mod vendor' removes the vendor directory under revision control.

Change-Id: Ifacba55c19f5391310ae247c36263c93e1249446
diff --git a/makefiles/lint/robot.mk b/makefiles/lint/robot.mk
new file mode 100644
index 0000000..9808602
--- /dev/null
+++ b/makefiles/lint/robot.mk
@@ -0,0 +1,41 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2017-2022 Open Networking Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# -----------------------------------------------------------------------
+
+ROBOT_FILES ?= $(error ROBOT_FILES= is required)
+
+LINT_ARGS ?= --verbose --configure LineTooLong:130 -e LineTooLong \
+             --configure TooManyTestSteps:65 -e TooManyTestSteps \
+             --configure TooManyTestCases:50 -e TooManyTestCases \
+             --configure TooFewTestSteps:1 \
+             --configure TooFewKeywordSteps:1 \
+             --configure FileTooLong:2000 -e FileTooLong \
+             -e TrailingWhitespace
+
+
+.PHONY: lint-robot
+
+lint : lint-robot
+
+lint-robot: vst_venv
+	source ./$</bin/activate \
+	    && set -u \
+	    && rflint $(LINT_ARGS) $(ROBOT_FILES)
+
+help::
+	@echo "  lint-robot           Syntax check robot sources using rflint"
+
+# [EOF]