add & update demos from zendframework/zf2 repo

[sasezaki]

@see zendframework/zendframework#2004
This demos autoload support only via composer install.

[jonathanmaron]

The demo directory, contain all the sample applications, is now again available in https://github.com/jonathanmaron/ZendServiceLiveDocx/tree/master/demos. They have all been ported to ZF2 RC2.

[ralphschindler]

@sasezaki I opted for @jonathanmaron's pull, can you let me know if anything in this pull request is outstanding?

[sasezaki]

I did do just below,

• copy from latest zendframework/zf2.git's demo
• create demos/ZendService/LiveDocx/_autoload.php
• s/Zend\Service/ZendService/ , rename Zend\Service\Demo\LiveDocx -> ZendServiceDemo\LiveDocx & directory resetting

& so my PRs would be apart from zf2 RC2 (out of date).
I don't have objection for jonathanmaron's PR. good for me.

Thanks for Thanks for consideration, @jonathanmaron & @ralphschindler.

[ralphschindler]

Awesome, thanks!