Add abilitiy to 'Save Raster style in Postgis database', just like is possible for Vector styles

[rduivenvoorde]

Feature description

More and more public (raster) data in the Netherlands also have QGIS style files in the zip.

When loading such files in a central Postgis database, it would be very cool to be able to save the/a style in the database as 'default style', just like is possible with Vectordata.
In that way, users would have an immediate styled view of the data.

For example the '5x5meter Land-use dataset':

is provided as geotiff, but accompanied with a qml style.

It seems not so difficult (???) to mimic the same behaviour as for vectors?

Though I see now that the public.layer_styles actually has a 'f_GEOMETRY_column'... not sure if it is wise to put a raster column in that one...

CREATE TABLE public.layer_styles (
	id serial4 NOT NULL,
	f_table_catalog varchar NULL,
	f_table_schema varchar NULL,
	f_table_name varchar NULL,
	f_geometry_column varchar NULL,
	stylename text NULL,
	styleqml xml NULL,
	stylesld xml NULL,
	useasdefault bool NULL,
	description text NULL,
	"owner" varchar(63) DEFAULT CURRENT_USER NULL,
	ui xml NULL,
	update_time timestamp DEFAULT CURRENT_TIMESTAMP NULL,
	"type" varchar NULL,
	CONSTRAINT layer_styles_pkey PRIMARY KEY (id)
);

Additional context

No response