[Owncloud] ownCloud Clone Script

[Arthur Schiwon]

Hey everybody,

upgrade testing of major releases becomes easy, when you can easily
setup a test instance and always go back to the state before doing the
upgrade.

It's also especially useful, when you can test upgrade with
real-world/production data.

Already before OC 5 I have had a script for me that allowed me to do so,
now for OC 6 I put it all together and made it configurable, so that it
may be useful for anybody out there.

My use case is: download a release tarball, take over config and
database from my production system. (In my case, data-folder will be
kept). 

Please find it in the administration repo on Github:
https://github.com/owncloud/administration/tree/master/ocClone

Please read the README file, and do a backup. Works for me and I
successfully went to 6 Beta 4, but who knows? Sometimes scripts are
eating kittens and things.

Cheers
Arthur

P.S.: i am not a Bash guru, reviews and improvements welcome.