Add ability to enable/disable dynamic subsystems

The CA installation process requires starting with the profile
subsystem disabled, then enabling it once profiles have been loaded
into the database.  Accordingly, to avoid hacks with hardcoded
offsets, add the "enabled" CS.cfg configuration parameter along with
methods to enable or disable a subsystem based on the subsystem ID.

A disabled subsystem does not have its `init` method called, but it
is still instantiated and added to the registry so that other code
can look up a subsystem by name and find out its class.

Subsystems are enabled by default.

This commit also removes an assumption that the subsystem config
sub-store names are sequential numbers beginning at `0`.

0 files changed, 0 insertions, 0 deletions