Call goimports as well as gofmt when doing a `make fmt` (#7148)

Closes #7147

Makefile

@@ -12,7 +12,7 @@ EXTERNAL_TOOLS=\
 	github.com/mitchellh/gox \
 	github.com/kardianos/govendor \
 	github.com/client9/misspell/cmd/misspell
-GOFMT_FILES?=$$(find . -name '*.go' | grep -v vendor)
+GOFMT_FILES?=$$(find . -name '*.go' | grep -v pb.go | grep -v vendor)
 
 GO_VERSION_MIN=1.11
 CGO_ENABLED?=0
@@ -194,6 +194,7 @@ fmtcheck:
 #@sh -c "'$(CURDIR)/scripts/gofmtcheck.sh'"
 
 fmt:
+	goimports -w $(GOFMT_FILES)
 	gofmt -w $(GOFMT_FILES)
 
 assetcheck:

audit/hashstructure_test.go

@@ -5,11 +5,12 @@ import (
 	"crypto/sha256"
 	"encoding/json"
 	"fmt"
-	"github.com/go-test/deep"
 	"reflect"
 	"testing"
 	"time"
 
+	"github.com/go-test/deep"
+
 	"github.com/hashicorp/vault/sdk/helper/certutil"
 	"github.com/hashicorp/vault/sdk/helper/salt"
 	"github.com/hashicorp/vault/sdk/helper/wrapping"

builtin/logical/pki/path_root.go

@@ -7,11 +7,12 @@ import (
 	"encoding/base64"
 	"encoding/pem"
 	"fmt"
-	"github.com/hashicorp/vault/sdk/helper/certutil"
 	"reflect"
 	"strings"
 	"time"
 
+	"github.com/hashicorp/vault/sdk/helper/certutil"
+
 	"github.com/hashicorp/errwrap"
 	"github.com/hashicorp/vault/sdk/framework"
 	"github.com/hashicorp/vault/sdk/helper/errutil"

helper/metricsutil/metricsutil.go

@@ -4,11 +4,12 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"strings"
+
 	"github.com/armon/go-metrics"
 	"github.com/hashicorp/vault/sdk/logical"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/expfmt"
-	"strings"
 )
 
 const (

physical/foundationdb/foundationdb_test.go

@@ -8,6 +8,7 @@ import (
 	"io/ioutil"
 	"os"
 	"testing"
+	"time"
 
 	"github.com/hashicorp/errwrap"
 	log "github.com/hashicorp/go-hclog"