There is no real use for groups in our API. Just use the name of
the file as the default group and be done with it...
Storing multiple groups with this API is problematic because it
forces flushing the file to disk multiple times, one for each group,
and it's just more performant if we use a prefix in the keys
to implement some form of logical separation.
This commit also makes the GKeyFile a temporary object. As we
always load the file from the file system in _load()
and we always replace its contents with a new dictionary in _save(),
there is no point in keeping the keyfile's internal data structures
stored in memory.
Save errors are now also propagated to adhere to the programming
practices of GObject
The component loader is a more generic and extensible mechanism
of loading components; modules are one type of component...
The idea is to make scripts and config files also be components,
loaded by plugins that inherit WpComponentLoader
* use the activate/deactivate system from WpObject,
which allows async activation and error reporting
* drop 'module' property, use 'core' from WpObject
* Use a more complete API to introspect SPA types
* Avoid the need for the Tables enumeration; the tables
are now registered with a string
* Avoid the need for initialization, work directly on spa_types
and other static data
* Allow working with Object pods that are not Params;
the PARAMS table was previously hardcoded in the pod implementation
* Add a different dynamic type registration system, closer to
how spa type works. The only regression is that we can no longer
register additional custom object fields (custom SPA_PROP_* for example),
but this feature can be re-added later
