Bump version to 0.8.15
Bump version to 0.8.15

dLobatog/dynflow,adamruzicka/dynflow,adamruzicka/dynflow,Dynflow/dynflow,adamruzicka/dynflow,Dynflow/dynflow,dLobatog/dynflow,dLobatog/dynflow,dLobatog/dynflow,Dynflow/dynflow,adamruzicka/dynflow,Dynflow/dynflow