v1.4.0-RC8

• Fixes #5076 - Pod validation of MaxPer constraint
• Fixes #5107 - Improve performance of zookeeper layer and groups (D481)
• Fixes #5087 - Generate DiscoveryInfo for pod container endpoints
• Fixes #5117 - Clarify rexray documentation
• Fixes #5144 - Define network-scope label for ipaddress.discovery.ports
• Fixes #5083 - Increase queue length for storage operations, helps large migrations
• Fixes #5116 - Pods allow duplicate endpoint ports
• Fixes #5084 - Doc link updates
• Fixes - Improve performance of dependency graph computations (D476)
• Improvement #5157 - PUT on /v2/apps has a PATCH semantic
• Improvement - NetworkSpec plugin API (D490)