public void nextPage(GuiManualHerblore manual){
  if (currentPage + 2 <= visiblePages.size()) {
    setPage(currentPage + 2,manual);
  }
}

public void nextPage ( GuiManualHerblore manual ) { if ( currentPage + 2 <= visiblePages . size ( ) ) { setPage ( currentPage + 2 , manual ) ; } }
flip to the next page
