• doc/configuration.html: add info about LDAP config options

Patch from Robert Foster rfoster@mountainvisions.com.au with a minor tweak to the description of $g_ldap_organization by me. (yeah fine, I still haven't gone to bed... but now I am)

git-svn-id: http://mantisbt.svn.sourceforge.net/svnroot/mantisbt/trunk@1749 <a class="text" href="/?p=mantisbt.git;a=object;h=f5dc347c">f5dc347c</a>-c33d-0410-90a0-b07cc1902cb9