[horde] Install horde from scratch with a git/cvs

[Robert McAuley]

To the Horde devs:

The echo line doesn't correct things entirely - core.php is not included by horde-fw-symlinks before it attempts to include Horde_Cli, so it doesn't solve the inclusion error.

To Thomas Bergen:

>From the Horde directory you're working in (e.g. mine is /var/www/html/horde-git/horde/), do a pwd, and add that to your php.ini's include directory.  Make sure that your php.ini also has the PEAR include directory. (on RHEL/CentOS this is /usr/share/pear)

For the docs, maybe it would be a good thing to break the copy/paste section to add a note saying you may have to do that.

- Rob