Add OpenLDAP and Berkeley DB packages

I use OpenLDAP (and Berkeley DB, which OpenLDAP implements) in one of my projects, so I thought I'd contribute back the package I'm using for it.

OpenLDAP is an open-source implementation of the LDAP directory-access server & protocol. Their project's homepage.

(hat tip to @beniwtv for adding OpenLDAP to boxparts, whose package file I based mine on)