FAQ --

[Q] How do I add/modify binary data?
[A] Create a LDAP::Mod object with the flag LDAP::LDAP_MOD_BVALUES as follows:

      entry = [
        LDAP::mod(LDAP::LDAP_MOD_ADD|LDAP_MOD_BVALUES, 'jpegPhoto', [jpeg_img]),
        LDAP::mod(LDAP::LDAP_MOD_ADD, 'cn', ['Takaaki Tateishi']),
        ...
      ]
      conn.add("dc=localhost, dc=localdomain", entry)


[Q] Is there shortcut method for adding/modifying entries.
[A] Yes, there is. You can directly give LDAP::Conn#add/modify hash data as follows:

      entry = {
        'objectclass' => ['top', 'person'],
        ...
      }
      conn.add("cn=foobar, dc=localhost, dc=localdomain", entry)

[Q] Can I use SASL authentication?
[A] No, you can't. It is because Ruby/LDAP doesn't provide such functionality
    correctly. I greatly appreciate you to implement it.
