Need to support Go 1.13

Teverts some stuff from 183c821; forgot that we need to support Go 1.13
up, and the deprecated stuff wasn't deprecated until Go 1.16

bench_test.go

@@ -6,7 +6,7 @@ package toml_test
 import (
 	"bytes"
 	"io/fs"
-	"os"
+	"io/ioutil"
 	"path/filepath"
 	"sort"
 	"strings"
@@ -114,7 +114,7 @@ func BenchmarkEncode(b *testing.B) {
 }
 
 func BenchmarkExample(b *testing.B) {
-	d, err := os.ReadFile("_example/example.toml")
+	d, err := ioutil.ReadFile("_example/example.toml")
 	if err != nil {
 		b.Fatal(err)
 	}

decode.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"math"
 	"os"
 	"reflect"
@@ -147,7 +148,7 @@ func (dec *Decoder) Decode(v interface{}) (MetaData, error) {
 
 	// TODO: parser should read from io.Reader? Or at the very least, make it
 	// read from []byte rather than string
-	data, err := io.ReadAll(dec.r)
+	data, err := ioutil.ReadAll(dec.r)
 	if err != nil {
 		return MetaData{}, err
 	}

decode_test.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io/ioutil"
 	"math"
 	"os"
 	"reflect"
@@ -30,7 +31,7 @@ func TestDecodeReader(t *testing.T) {
 }
 
 func TestDecodeFile(t *testing.T) {
-	tmp, err := os.CreateTemp("", "toml-")
+	tmp, err := ioutil.TempFile("", "toml-")
 	if err != nil {
 		t.Fatal(err)
 	}

parse.go

@@ -378,13 +378,13 @@ func (p *parser) valueArray(it item) (interface{}, tomlType) {
 		val, typ := p.value(it, true)
 		array = append(array, val)
 		types = append(types, typ)
-		_ = types
 
 		// XXX: types isn't used here, we need it to record the accurate type
 		// information.
 		//
 		// Not entirely sure how to best store this; could use "key[0]",
 		// "key[1]" notation, or maybe store it on the Array type?
+		_ = types
 	}
 	return array, tomlArray
 }