title: Extract, format and separate JSON already stored in a data frame column
body: <p>How might I parse and process JSON that already lives inside a data frame? </p>
  
  <p>Sample data:</p>
  
  <pre><code>df &lt;- data.frame(
      id = c("x1", "x2"), 
      y = c('[{"Property":"94","Value":"Error"},{"Property":"C1","Value":"Found Match"},{"Property":"C2","Value":"Address Mismatch"}]', '[{"Property":"81","Value":"XYZ"},{"Property":"D1","Value":"Blah Blah"},{"Property":"Z2","Value":"Email Mismatch"}]')
  )
  </code></pre>
  
  <p>I want to extract, format and separate the raw JSON in column <code>y</code> into orderly columns, ideally with <code>library(jsonlite)</code>.</p>
  
  <p>Thanks in advance!</p>