Add new QingStor remote

Add new package qingstor to support QingStor API.

Add new unit test for its and tested through; But I commented
on some tests case because of some of the features of QingStor.

Add new docs for it.

fs/all/all.go

@@ -14,6 +14,7 @@ import (
 	_ "github.com/ncw/rclone/hubic"
 	_ "github.com/ncw/rclone/local"
 	_ "github.com/ncw/rclone/onedrive"
+	_ "github.com/ncw/rclone/qingstor"
 	_ "github.com/ncw/rclone/s3"
 	_ "github.com/ncw/rclone/sftp"
 	_ "github.com/ncw/rclone/swift"

fs/test_all.go

@@ -103,6 +103,11 @@ var (
 			SubDir:   false,
 			FastList: false,
 		},
+		{
+			Name:     "TestQingStor:",
+			SubDir:   false,
+			FastList: false,
+		},
 	}
 	binary = "fs.test"
 	// Flags