Update version to 1.2.21

Update version to 1.2.21

Update version to 1.2.20

Update version to 1.2.19

Update version to 1.2.18

Update version to 1.2.17

Update changelog to 1.2.16

Update changelog to 1.2.15

Update changelog to 1.2.14

Update changelog to 1.2.13