Adds migrations for new models

internal/database/migrations/2_feed.sql

@@ -0,0 +1,11 @@
+-- +migrate Up
+CREATE table feed (
+  id INTEGER PRIMARY KEY,
+  name text NOT NULL,
+  url text NOT NULL UNIQUE,
+  userId text NOT NULL,
+  FOREIGN KEY (userId) REFERENCES user(id)
+);
+
+-- +migrate Down
+DROP TABLE feed;