v2.8.0-stable

OpenBMC Dev Tag https://github.com/openbmc/openbmc/releases/tag/2.8.0
OpenBMC test branch https://github.com/openbmc/openbmc-test-automation/tree/2.8.0

Testing Report https://lists.ozlabs.org/pipermail/openbmc/2020-June/021961.html

Yocto refresh to "Dunfell" version 3.1
Redfish support for: full certificate management, complete LDAP management, full sensor support, event service schema, task schema
Move to Redfish Specification 1.9.0
Redfish support for 2019.4 Schemas
GUI enhancements: LDAP, certificate management

Changes in test:

Code fixes and documentation updates