wip for db_migrations for core schema

sql/pgsql/migrations/84.sql

@@ -0,0 +1,22 @@
+begin;
+
+create table ttrss_linked_instances (id serial not null primary key,
+	last_connected timestamp not null,
+	last_status_in integer not null,
+	last_status_out integer not null,
+	access_key varchar(250) not null unique,
+	access_url text not null);
+
+create table ttrss_linked_feeds (
+	feed_url text not null,
+	title text not null,
+	created timestamp not null,
+	updated timestamp not null,
+	instance_id integer not null references ttrss_linked_instances(id) ON DELETE CASCADE,
+	subscribers integer not null);
+
+drop table ttrss_scheduled_updates;
+
+update ttrss_version set schema_version = 84;
+
+commit;