Integration Branch for develop: 2019 week 17
The following Merge Requests are included:
- MR 557 : Implement CDRX in FDD mode
- MR 571 : Improvement on documentation
- MR 572 : Fix CU/DU protocol split
- MR 574 : Fix a flexran free issue
- MR 578 : CI -- Improve OAI UE testing with USRP
