Method to plot top vertices barplot using results of computeGraphMetric

[grigory93]

prototype code is:

createTopMetricPlot <- function(data, metric, xlab='Officer', ylab='Degree', title) {
  p = ggplot(data) +
    geom_bar(aes_string("key", metric, fill="key"), stat='identity') +
    labs(x=xlab,y=ylab,title=title) +
    ggthemes::theme_tufte() + 
    theme(legend.position='none', 
          axis.text.x = element_text(size=16, angle = 315, vjust = 1), 
          plot.title = element_text(size=20),
          axis.ticks = element_blank())
  
  return(p)
  }