title: Plot multiple lines with sorted DataFrame fields by time stamp
body: <p>I am looking for an elegant solution to plot lines via Plots.jl, sorted by time stamp</p>
  
  <p>I want each line to represent closeAsk (Float64) data field by different year, judging by time stamp year i.e., 2002, 2003, etc.</p>
  
  <p>So, if we have data stamp from 2002 through 2019 as the below example, we should have <strong>18</strong> lines on a graph.</p>
  
  <pre><code>julia&gt; df2 = df[[:closeAsk, :time]]  
  5000×2 DataFrame  
  │ Row  │ closeAsk │ time                        │  
  │      │ Float64  │ String                      │  
  ├──────┼──────────┼─────────────────────────────┤  
  │ 1    │ 0.9949   │ 2002-11-28T22:00:00.000000Z │  
  │ 2    │ 0.995    │ 2002-11-30T22:00:00.000000Z │  
  ⋮  
  │ 4998 │ 1.13414  │ 2019-02-06T22:00:00.000000Z │  
  │ 4999 │ 1.13244  │ 2019-02-07T22:00:00.000000Z │  
  │ 5000 │ 1.13251  │ 2019-02-10T22:00:00.000000Z │  
  </code></pre>
  
  <p>The way I am thinking of is to use comprehension to create a set of DataFrames representing the closeAsk field for each year, which we feed to plot(x, y), where y is an array of those butchered DataFrames.</p>
  
  <p>Thanks in advance.</p>