Changed the Zend library and adapted the code to usage of namespacing

- Switched over to Zend Framework 2
- Modified all the classes to use namespacing to ease work with the ZF2 lib
- A couple optimizations and corrections over the code
Added new B0 test

- This "test" will print all documents and its properties on a table
- Useful and good to use with the other tests
Deleting previously removed files
Corrected namespacing in test B3 and Utilities
Separated date conversion functions into its own class

- Created a Nuxeo\Utilities\DateConverter class to separate the
  date conversion functions and group them into a single, concrete
  class.
Code clean-up, we now follow PSR2 standard