Add placeholder text (fixes #53)

Author: fsck

static/index.html

@@ -46,7 +46,7 @@
                   <div class="form-check">
                     <input class="form-check-input" type="radio" name="type" id="type_pubkey" value="PubKey">
                     <label class="form-check-label" for="type_pubkey">Raw SSH PublicKey:</label>
-                    <textarea class="reveal-if-active form-control" name="sshpublic" rows="1" cols="2000">ssh-rsa AAAA... user@enoflag</textarea>
+                    <textarea class="reveal-if-active form-control" name="sshpublic" rows="1" cols="2000" placeholder="ssh-rsa AAAA... user@enoflag"></textarea>
                   </div>
                   <div class="form-group">
                     <label for="authkey">AUTHKEY:</label>