ggheatmap<-function(df, x=NULL, y=NULL, value=NULL){

  if (is.null(x)){x=colnames(df)[1]}
  if (is.null(y)){y=colnames(df)[2]}
  if (is.null(value)){value=colnames(df)[3]}

  order<-clustsort(df %>% spread(y,value))

  df %>%
    ggplot(aes_string(x, y, fill=value))+
    scale_x_discrete(limits=order$x)+
    scale_y_discrete(limits=order$y)+
    labs(x=x, y=y)+
    theme_heatmap()
}