public ldap search features implemented

hi all,

i've just committed some code enabling searching of public ldap servers from roundcube. there may be a delay until the code is available via the public sourceforge cvs servers, but it should be there in the next day or so.

the ldap search button will not work until you have configured a public ldap server in the config/main.inc.php file. there is an example configuration for the Verisign directory in config/main.inc.php.dist.

i'd appreciate some testing and bug hunting :-)

also, the ldap icon in the addressbook page reflects my complete lack of artistic abilities - please, could someone with some skills replace it?

cheers justin