text: Title: Adding additional colorbar functionality 
  Body: Hello,
  So I have never made edits to any package before but I was frustrated by the lack of changes to colorbar parameters that were in the original code, or at least from what I could figure out. Thus I decided to add a couple extra line to the radardisplay.py script under the plot_colorbar:
  
  def plot_colorbar(self, **label_size =22,ticklabel_size = 22,fraction=0.046,** mappable=None, 		field=None, label=None,orient='vertical', cax=None, ax=None, fig=None,ticks=None, 			ticklabs=None):  
          Plot a colorbar.
  
          Parameters
         
          mappable : Image, ContourSet, etc.
              Image, ContourSet, etc to which the colorbar applied.  If None the
              last mappable object will be used.
          field : str
              Field to label colorbar with.
  	**label_size : int
  		Font size of the colorbar label. Default is 22
  	ticklabel_size : int
  		Font size for the tick label on the colorbar. Default is 22
  	Fraction : int
  		Fraction of original axes to use for colorbar. Default of 0.046 seems to work well from my testing**
          label : str
              Colorbar label.  None will use a default value from the last field
              plotted.
          orient : str
              Colorbar orientation, either 'vertical' [default] or 'horizontal'.
          cax : Axis
              Axis onto which the colorbar will be drawn.  None is also valid.
          ax : Axes
              Axis onto which the colorbar will be drawn. None is also valid.
          fig : Figure
              Figure to place colorbar on.  None will use the current figure.
          ticks : array
              Colorbar custom tick label locations.
          ticklabs : array
                  Colorbar custom tick labels.
          
          if fig is None:
              fig = plt.gcf()
          if mappable is None:
              mappable = self.plots[-1]
          if label is None:
              if field is None:
                  field = self.plot_vars[-1]
              label = self._get_colorbar_label(field)
  
          **cb = fig.colorbar(mappable, orientation=orient, ax=ax, cax=cax,fraction=fraction)
          cb.ax.tick_params(labelsize=ticklabel_size)**
          if ticks is not None:
              cb.set_ticks(ticks)
          if ticklabs:
              cb.set_ticklabels(ticklabs)
          **cb.set_label(label, fontsize = label_size)**
  
  	
  
          self.cbs.append(cb)
  
  I'm not sure how to contribute this to the source code or even if this is the best way to do it but it works well for what I needed. So I thought I'd share it here so maybe it could be added in the future.