Comments in a multiline array cause parse error

An array of the form:

     [1, # wow
      2, # such items
      3, # so array
     ]

panics with a parse error, "unterminated array" This should parse according to https://github.com/mojombo/toml#array.

The following unit test demonstrates the issue:

```
diff --git a/parser_test.go b/parser_test.go
index 7f7888e..629e0a6 100644
--- a/parser_test.go
+++ b/parser_test.go
@@ -170,6 +170,20 @@ func TestNewlinesInArrays(t *testing.T) {
        })
 }
 
+func TestArrayWithExtraComma(t *testing.T) {
+       tree, err := Load("a = [1,\n2,\n3,\n]")
+       assertTree(t, tree, err, map[string]interface{}{
+               "a": []int64{int64(1), int64(2), int64(3)},
+       })
+}
+
+func TestArrayWithExtraCommaComment(t *testing.T) {
+       tree, err := Load("a = [1, # wow\n2, # such items\n3, # so array\n]")
+       assertTree(t, tree, err, map[string]interface{}{
+               "a": []int64{int64(1), int64(2), int64(3)},
+       })
+}
+
 func TestMissingFile(t *testing.T) {
        _, err := LoadFile("foo.toml")
        if err.Error() != "open foo.toml: no such file or directory" {

```