title: Convert AsIs to numeric separated by coma in data frame
body: <p>I have such data frame:</p>
  
  <pre><code>structure(list(P1 = c("Mark", "Katrin", "Kate", "Hank", "Tom", 
  "Marcus"), P2 = c("Tim", "Greg", "Seba", "Teqa", "Justine", "Monica"
  ), clique = structure(list(`930` = integer(0), `2090` = integer(0), 
      `3120` = c(2L, 3L, 231L), `3663` = integer(0), `3704` = integer(0), 
      `4156` = c(19L, 27L)), .Names = c("930", "2090", "3120", 
  "3663", "3704", "4156"), class = "AsIs")), .Names = c("P1", "P2", 
  "clique"), row.names = c(930L, 2090L, 3120L, 3663L, 3704L, 4156L
  ), class = "data.frame")
  </code></pre>
  
  <p>And I have a problem with the last column called <code>clique</code>. I would like to convert this column to numeric values separated by come in one column or the best option would be to transform <code>integer(0)</code> to NAs and put the numbers in separate columns. Just keep one number in each column.
  I will accept both solutions. </p>
  
  <p>example data:</p>
  
  <pre><code>P1  P2  clique
  Mark    Tim integer(0)
  Katrin  Greg    integer(0)
  Kate    Seba    c(2, 3, 231)
  Hank    Teqa    integer(0)
  Tom Justine integer(0)
  Marcus  Monica  c(19, 27)
  
  &gt; class(data$clique)
  [1] "AsIs"
  </code></pre>
  
  <p>Desired output:</p>
  
  <pre><code> P1      P2    clique
  Mark     Tim      NA    
  Katrin   Greg     NA    
  Kate     Seba    2,3,231
  Hank     Teqa     NA
  Tom      Justine  NA    
  Marcus   Monica  19,27
  </code></pre>
  
  <p>or</p>
  
  <pre><code>P1      P2    clique New_column1 New_column2
  Mark    Tim          
  Katrin  Greg          
  Kate    Seba      2        3          231
  Hank    Teqa          
  Tom     Justine          
  Marcus  Monica    19       27
  </code></pre>