Add missing documentation for timeout option

Author: mantoni

README.md

@@ -29,6 +29,8 @@ lambda.invoke('some-lambda', { some: 'event' }, callback);
     variable.
   - `timeout`: The default Lambda timeout to use in milliseconds. Defaults
     to 5 seconds.
+  - `memory`: The default Lambda memory to use in MB. Defaults to 128 MB. This
+    will set `--max-old-space-size` on Lambda processes.
   - `max_idle`: The idle timeout to use in milliseconds. If a function is
     not invoked for this time, the process gets destroyed. Defaults to 1 hour.
 - `lambda.invoke(lambda_name, event[, options][, callback])`: Invokes the named
@@ -57,8 +59,7 @@ Lambda function are invoked with `(event, context[, callback])` where the
 - `invokedFunctionArn`: The function ARN, build from the `AWS_REGION`
   (defaulting to `us-east-1`), `STUDIO_AWS_ACCOUNT` (defaulting to
   `000000000000`) and the Lambda function name.
-- `memoryLimitInMB`: The configured memory limit. This is currently not
-  enforced.
+- `memoryLimitInMB`: The configured memory limit.
 - `awsRequestId`: The AWS request ID, either from `options` or generated.
 - `getRemainingTimeInMillis()`: Returns the remaining time until the Lambda
   function times out.