title: Add dataframe name in new column when using bind_rows R
body: <p>I feel like this should be obvious but I can't seem to find any information on this!</p>
  <p>I would like to use bind_rows to combine two dfs, and have a new ID column created with the names of the df that data was from.</p>
  <pre><code>new_df &lt;- bind_rows(apple_df, tiger_df, .id = &quot;???&quot;)
  </code></pre>
  <p>So new_df$id should contain &quot;apple_df&quot; and &quot;tiger_df&quot; as values.</p>
  <p>I've tried .id = &quot;src&quot;, .id = &quot;id&quot; but nothing seems to work. The closest is .id = &quot;id&quot; but I get the index number as a result.</p>
  <p>I also want to avoid overcomplicating this as much as possible. It seems like it should be a basic feature to have .id = &quot;nameofobjectsbeingbound&quot;. Thanks!</p>