RTEditor/src/main/java/com/onegravity/rteditor/RTOperationManager.java
private void push(Operation op, Stack<Operation> stack) {
        if (stack.size() >= MAX_NR_OF_OPERATIONS) {
            stack.remove(0);
        }
        stack.push(op);
    }
private void push(Operation op, Stack<Operation> stack) {
        if (stack.size() >= MAX_NR_OF_OPERATIONS) {
            stack.remove(0);
        }
        stack.push(op);
    }
****************************************** Private Methods *******************************************