#197 Diagnostics are unreliable during start-up and shut-down

[Vidar Hasfjord]

The diagnostics groups require static initialization and suffer from the undefined initialization order for globals (this is standard-compliant). This means that a global component producing diagnostics during initialization, and being initialized arbitrarily before the diagnostics group it uses, will not have its diagnostics messages shown. The same goes for destruction and shut-down.

Ideally, the diagnostics groups should be initialized on demand (lazy) and outlive any component using them.