Add examples to build REST-endpoints around of extBase-objects

Add examples to build REST-endpoints around of extBase-objects

Support of TYPO3 7.6 (LTS)

Now, the restler_examples-Extension supports TYPO3 7.6 (LTS).

adapt examples for internal REST-API-endpoints

adapt examples for internal REST-API-endpoints:

• internal REST-API-endpoints now return stdClass-objects instead of array's (which increases the usability)
• given GET/Post-parameters for internal REST-API-endpoints can be of type array OR stdClass

Added examples to show the new features of the REST-API-Client

Added examples to show the new features of the REST-API-Client, which can be used to call (internal) REST-API-Endpoints (which are configured in restler).