title: Change column name based on named vector (R)
body: <p>I have the following dataframe:</p>
  <pre><code>   a b c d e f g h i j
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
  </code></pre>
  <p>And the following vector (or dataframe)</p>
  <pre><code>sample     name
  a          1
  b          2
  c          3
  d          4
  e          5
  f          6
  g          7
  h          8
  i          9
  j          10
  </code></pre>
  <p>I want to rename the columns on the first dataframe, based on the second dataframe:</p>
  <pre><code>   1 2 3 4 5 6 7 8 9 10
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
     1 1 1 1 1 1 1 1 1 1
  </code></pre>