Authors: Bo Zhao, Marwan Hammouda, Thomas Schlichter (Fraunhofer IIS)

- CMakeLists modification: add QtWidgets library, add new source files, MOC (Meta-Object Compiler) on the given source file
- build_oai modification
- Activate new GUI with Qt on the UE side
- 2 x 3 widget with I/Q sample for PDSCH
- Drop-down list implementation