title: convert hex to binary in javascript
body: <p>I need to convert hex into binary using javascript.</p>
  
  <p>example:
  21 23 00 6A D0 0F 69 4C E1 20 </p>
  
  <p>should result in:
  ‭0010000100100011000000000110101011010000000011110110100101001100‬</p>
  
  <p>Does anyone know of a javascript library I might use to accomplish this?</p>
  
  <p>Harriet</p>