Added the index_rename command

Author: dancannon

query.go

@@ -100,6 +100,7 @@ type WriteResponse struct {
 	Updated       int
 	Unchanged     int
 	Replaced      int
+	Renamed       int
 	Deleted       int
 	GeneratedKeys []string    `gorethink:"generated_keys"`
 	FirstError    string      `gorethink:"first_error"` // populated if Errors > 0

query_table.go

@@ -89,6 +89,22 @@ func (t Term) IndexList(args ...interface{}) Term {
 	return constructMethodTerm(t, "IndexList", p.Term_INDEX_LIST, args, map[string]interface{}{})
 }
 
+type IndexRenameOpts struct {
+	Overwrite interface{} `gorethink:"overwrite,omitempty"`
+}
+
+func (o *IndexRenameOpts) toMap() map[string]interface{} {
+	return optArgsToMap(o)
+}
+
+// IndexRename renames an existing secondary index on a table. If the optional
+// argument overwrite is specified as True, a previously existing index with the
+// new name will be deleted and the index will be renamed. If overwrite is False
+// (the default) an error will be raised if the new index name already exists.
+func (t Term) IndexRename(oldName, newName interface{}, optArgs ...IndexRenameOpts) Term {
+	return constructMethodTerm(t, "IndexRename", p.Term_INDEX_RENAME, []interface{}{oldName, newName}, map[string]interface{}{})
+}
+
 // Get the status of the specified indexes on this table, or the status of all
 // indexes on this table if no indexes are specified.
 func (t Term) IndexStatus(args ...interface{}) Term {

query_table_test.go

@@ -198,6 +198,20 @@ func (s *RethinkSuite) TestTableIndexDelete(c *test.C) {
 	c.Assert(response, JsonEquals, map[string]interface{}{"dropped": 1})
 }
 
+func (s *RethinkSuite) TestTableIndexRename(c *test.C) {
+	Db("test").TableDrop("test").Exec(sess)
+	Db("test").TableCreate("test").Exec(sess)
+	Db("test").Table("test").IndexCreate("test").Exec(sess)
+
+	// Test index rename
+	query := Db("test").Table("test").IndexRename("test", "test2")
+
+	res, err := query.RunWrite(sess)
+	c.Assert(err, test.IsNil)
+
+	c.Assert(res.Renamed, JsonEquals, 1)
+}
+
 func (s *RethinkSuite) TestTableChanges(c *test.C) {
 	Db("test").TableDrop("changes").Exec(sess)
 	Db("test").TableCreate("changes").Exec(sess)