draw_river_desc(ncfile, values, riverns)
  values= [dimname]|[vardimname]|[value]:[basinvals]:[upstreamvals]:[mapvalues]:
      [gtit]:[kindfig]:[legvals]:[figuren]:[closefig]
    'X/Y'|[dimname]|[vardimname]|[value]: ',', list for each basic dimension '|' separated of:
      [dimname]= name of the dimension in the file for 'X' and 'Y' axis
      [vardimname]: name of the variable with the values for the dimension in the file
    [value]: which value of the given dimension is required:
      * [integer]: which value of the dimension
      * -1: all along the dimension
      * -9: last value of the dimension
      * [beg]:[end] slice from [beg] to [end]
      * NOTE, no dim name all the dimension size
      No value takes all the range of the dimension
    [basinsvals]= [colorline] colors for the border line of each basin
    [basincolor]: ',' list of colors of the line to use to mark the basins contours (single value also possible)
    [upstreamcolor]: colorbar to use to plot the basins upstream values
    [mapvalues]= map characteristics: [proj],[res]
      see full documentation: http://matplotlib.org/basemap/
      [proj]: projection
        * 'cyl', cilindric
        * 'lcc', lambert conformal
      [res]: resolution:
        * 'c', crude
        * 'l', low
        * 'i', intermediate
        * 'h', high
        * 'f', full
    [gtit]= title of the graph ('|', for spaces)
    [kindfig]= kind of figure (png, ps, pdf)
    [legvals]=[locleg]|[fontsize]:
      [locleg]: location of the legend (0, autmoatic)
        1: 'upper right', 2: 'upper left', 3: 'lower left', 4: 'lower right',
        5: 'right', 6: 'center left', 7: 'center right', 8: 'lower center',
        9: 'upper center', 10: 'center'
      [fontsize]: font size for the legend (auto for 12)
    [figuren]= name of the figure
    [closefig]= whether figure should be closed or not
  ncfile= file to use
  riverns= ',' list of the name of the rivers to plot