cosmic-6.4.7

Full Changelog

Closed issues:

• When using a network offering with remote gateway, it's not possible to deploy a VM as gateway #863
• Prevent live migrating to host that doesn't meet tag or affinity group #596
• Clustered Mgt server: on upgrade another mgt server is detected with the same ip #472

Merged pull requests:

• Implement is_gateway_vm property #872 (remibergsma)
• Remove SSL #871 (sanderv32)
• Bump netty-all #870 (sanderv32)