Yubikey client library development files

 YubiKeys are USB tokens that act like keyboards and generate one-time
 passwords (OTPs). The tokens are produced and sold by Yubico.
 .
 This library is used for talking to an online validation server such
 as yubikey-server-c, yubikey-server-php or yubikey-server-j.
 .
 This package contains the necessary files for developers, and a
 command line tool "ykclient" to perform OTP queries from the shell.