plot_mrb: Plot MrBayes log file
In kmiddleton/kmmisc: KM Misc

This function plots a MrBayes log file. Either a .mcmc file or a .p file is acceptable, and the file type will be determined automatically. If an mcmc file is chosen, the average standard deviation of the split frequencies is plotted. If a p file is chosen, the log-likelihood is plotted.

1	plot_mrb(logfile = NULL, burnin = 0.25, lwd = 1.5, cutoff = 0.05, ideal = 0.01)

`logfile`	The MrBayes log file to be loaded. If `logfile = NULL`, then the user is prompted to choose a file.
`burnin`	The burnin period, either specified in absolute number of generations or as a fraction of the total number of generations (`burnin` < 1). The default is 0.25.
`lwd`	Line width for the plot. Defaults to 1.5.
`cutoff`	The minimum value for acceptable convergence. Only applicable for mcmc files. Defaults to 0.05.
`ideal`	The ideal value for acceptable convergence. Only applicable for mcmc files. Defaults to 0.01.