[Observium] Observium CE 19.8 Release

We've just released the new version of Observium CE, 19.8. This release is based on SVN revision 10000 and includes 580 separate commits covering ~50k changed lines of code since the previous release.

Upgrade instructions are at https://www.observium.org/docs/updating/#upgrade-to-latest-major-release

Changelog is at https://www.observium.org/svn.log

Thanks, Adam.