title: Plotting barplot with bars by grouped/colored by group names
body: <p>Well with this dataset in CSV format, </p>
  
  <pre><code>GO Biological Process,regulation of lipid metabolic process,1.87E-35
  GO Biological Process,acute inflammatory response,3.21E-37
  GO Biological Process,response to insulin stimulus,1.05E-38
  GO Biological Process,steroid metabolic process,4.19E-39
  GO Biological Process,cholesterol metabolic process,1.19E-40
  GO Biological Process,cellular response to chemical stimulus,5.87E-42
  GO Biological Process,alcohol metabolic process,5.27E-43
  GO Biological Process,sterol metabolic process,2.61E-43
  GO Biological Process,lipid homeostasis,1.12E-44
  GO Biological Process,response to peptide hormone stimulus,1.29E-45
  GO Biological Process,monocarboxylic acid metabolic process,2.33E-54
  GO Biological Process,cellular ketone metabolic process,5.46E-74
  GO Biological Process,carboxylic acid metabolic process,2.41E-76
  GO Biological Process,organic acid metabolic process,5.30E-79
  Pathway Commons,FOXA transcription factor networks,7.40E-61
  Pathway Commons,FOXA2 and FOXA3 transcription factor networks,1.39E-64
  Transcription Factor Targets,"Targets of HNF6, identified by ChIP-chip in hepatocytes",1.77E-32
  Transcription Factor Targets,"Targets of HNF1alpha, identified by ChIP-chip in hepatocytes",3.87E-65
  Transcription Factor Targets,"Targets of HNF4alpha, identified by ChIP-chip in hepatocytes",1.38E-131
  </code></pre>
  
  <p>I would like to be able to create a plot (barplot?) that looks like this :
  <img src="https://i.stack.imgur.com/P1Msu.png" alt="enter image description here"></p>
  
  <p>where the three different groups in column 1 are grouped together with the same color and the 3rd column is sorted from biggest to smalest. 
  The plot above is made with excel but I would like to be able to make it properly in R. 
  So far all I am getting is the 2nd and 3nd column plotted, I can't get the bars grouped by the 1st column. </p>
  
  <hr>
  
  <p>Well I have tried ggplot as recommended. This is what I got (it looks brilliant btw) :</p>
  
  <pre><code>library(ggplot2)
  ggplot(tmp, aes(x=tmp$V2, y=log(tmp$V3), fill=tmp$V1)) +
  geom_bar(stat="identity") +
  coord_flip() +
  scale_y_log()
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/P1Msu.png" alt="how"></p>
  
  <p>However, I need to find out how to "reverse" the axis such as [0, 1e-130] (eg. the bars go from left to right like in my example above)</p>