Scripts to setup LDAP and phpldapadmin docker images

Note: I'm new to docker so not sure whether there is a better way to do this.

Run `./setup.sh` once, it will download the images for slapd and phpldapadmin.

Then use `./start.sh` to run the containers.
`./stop.sh` will stop and reset the containers (starting from scratch)

This is already enough to get started with an LDAP server and link it to ownCloud :smile: 

See `start.sh` contents for credentials / DN.

@blizzz you can probably publish your zombie generator scripts here later

CC @DeepDiver1975 @felixboehm