docs: oas (#197)

Adds OpenAPI specification of Storefront and Admin APIs.
Updates docs project.

docs-util/fixture-gen/helpers/admin-seeder.js

@@ -0,0 +1,17 @@
+const Scrypt = require("scrypt-kdf");
+const { User } = require("@medusajs/medusa");
+
+module.exports = async (connection, data = {}) => {
+  const manager = connection.manager;
+
+  const buf = await Scrypt.kdf("secret_password", { logN: 1, r: 1, p: 1 });
+  const password_hash = buf.toString("base64");
+
+  await manager.insert(User, {
+    id: "admin_user",
+    email: "admin@medusa.js",
+    api_token: "test_token",
+    password_hash,
+    ...data,
+  });
+};