all: fix plugin import ordering (#1717)

Got a bit messed up with stb lib "context" usage.

plugin/template/template.go

@@ -2,6 +2,7 @@ package template
 
 import (
 	"bytes"
+	"context"
 	"regexp"
 	"strconv"
 	gotmpl "text/template"
@@ -11,8 +12,6 @@ import (
 	"github.com/coredns/coredns/plugin/pkg/upstream"
 	"github.com/coredns/coredns/request"
 
-	"context"
-
 	"github.com/miekg/dns"
 )
 

plugin/template/template_test.go

@@ -1,6 +1,7 @@
 package template
 
 import (
+	"context"
 	"fmt"
 	"regexp"
 	"testing"
@@ -10,8 +11,6 @@ import (
 	"github.com/coredns/coredns/plugin/pkg/fall"
 	"github.com/coredns/coredns/plugin/test"
 
-	"context"
-
 	"github.com/mholt/caddy"
 	"github.com/miekg/dns"
 )