Woocommerce Payment Gateway Based Fees 5.0

* Modified bugfix subscription plugin - remove our fees from existing order on renewal and manual payment see github.com
* EU VAT plugin temporary fix: does not take care of is_vat_exempt of a saved order (see classes\class-wc-order-add-fees.php)
* WC 3.0 compatibility adjustments

* Bugfix subscription plugin pay for order page - adds all fees from existing order (we do not recognise our fees any longer)

* Make plugin ready for WC 3.0.0 - great version junp of WC
- for backwards comp move php classes to /v2614
- remove code for versions <= 2.6.14 from php class code in /classes
- add CRUD access introduced with WC 3.0.0
- refactor and optimize code
- supress fee lines with calculated value 0

* As we moved all code < WC 2.6.14 to own folder, all classes, properties and methods in folder classes have @since 3.0.0 by default