title: Julia equivalent of dplyr's bind_cols and bind_rows
body: <p>Is there a Julia equivalent of dplyr's bind_cols and bind_rows? Specifically, I'm looking for a bind_rows function which will match column names regardless of order and fill in NA's for non-matching columns</p>
  
  <p>Edit: R Example of both:</p>
  
  <pre><code>library(dplyr)
  df1 = data.frame(a = 1, b = 1)
  df2 = data.frame(b = 1, c = 1)
  df3 = data.frame(c = 1, d = 1)
  
  bind_rows(df1, df2)
  
     a b  c
  1  1 1 NA
  2 NA 1  1
  
  bind_cols(df1, df3)
  
    a b c d
  1 1 1 1 1
  </code></pre>