Lint (#700)

* adjust GNUmakefile by using ... wildcard

go command excludes vendored packages from ... wildcard Go1.9 or later

* fix vet warnings

* fmt

GNUmakefile

@@ -15,7 +15,7 @@
 	clean
 
 SRCS = $(shell git ls-files '*.go')
-PKGS = ./. ./cache ./commands ./config ./models ./oval ./report ./scan ./util 
+PKGS = $(shell go list ./...)
 VERSION := $(shell git describe --tags --abbrev=0)
 REVISION := $(shell git rev-parse --short HEAD)
 LDFLAGS := -X 'main.version=$(VERSION)' \
@@ -40,11 +40,11 @@ install: main.go dep pretest
 
 lint:
 	@ go get -v github.com/golang/lint/golint
-	$(foreach file,$(SRCS),golint $(file) || exit;)
+	golint $(PKGS)
 
 vet:
 	#  @-go get -v golang.org/x/tools/cmd/vet
-	echo $(PKGS) | xargs go vet || exit;
+	go vet ./... || exit;
 
 fmt:
 	gofmt -s -w $(SRCS)
@@ -58,7 +58,7 @@ test: pretest
 	go install
 	echo $(PKGS) | xargs go test -cover -v || exit;
 
-unused :
+unused:
 	$(foreach pkg,$(PKGS),unused $(pkg);)
 
 cov: