This commit adds a new initialization priority `FreezeNamespaces` that is run
last and moves all calls to `Namespace::Freeze()` there. This allows all other
initialization functions to still update namespaces without the use of the
`overrideFrozen` flag.
It also moves the initialization of `System.Platform*` and `System.Build*` to
an initialize function so that these can also be set without setting
`overrideFrozen`.
This is preparation for a following commit that will make the frozen flag in
namespaces finial, no longer allowing it to be overriden (freezing the
namespace will disable locking, so performing further updates would be unsafe).
Example:
categories = [ "DbCatProgramStatus", "DbCatState" ]
The old method with constants and OR is still supported but deprecated.
refs #11445fixes#12024