[WCM] Embedded PHPCR Shell

Replaces existing commands with embedded PHPCR Shell.

Depends on: https://github.com/phpcr/phpcr-shell/pull/40

For example

````
$ php app/console phpcr node:list / # commands with arguments can be entered without quotes
$ php app/console phpcr "ls -L2" # commands with options must be quoted
$ php app/console phpcr node-type:list
$ php app/console phpcr "SELECT * FROM [nt:unstructured]" # queries must be quoted
````

okay, lets do like you currently propose for the current iteration and maybe change to a requirement on the release after (the 1.3 release of the bundle)

created https://github.com/phpcr/phpcr-shell/issues/79 to discuss the dependencies.