Add javadoc.

bramble-api/src/main/java/org/briarproject/bramble/api/io/TimeoutMonitor.java

@@ -4,5 +4,12 @@ import java.io.InputStream;
 
 public interface TimeoutMonitor {
 
+	/**
+	 * Returns an {@link InputStream} that wraps the given stream and allows
+	 * read timeouts to be detected.
+	 *
+	 * @param timeoutMs The read timeout in milliseconds. Timeouts will be
+	 * detected eventually but are not guaranteed to be detected immediately.
+	 */
 	InputStream createTimeoutInputStream(InputStream in, long timeoutMs);
 }