Merge remote-tracking branch 'origin/develop-CSI' into develop-CSI-Measurements

ci-scripts/cls_oaicitest.py

...cripts/conf_files/enb.band38.lte_2x2.100PRB.usrpn310.conf

...ts/conf_files/enb.band38.lte_2x2_tm2.100PRB.usrpn310.conf

...cripts/conf_files/enb.band38.nsa_2x2.100PRB.usrpn310.conf

...cripts/conf_files/gnb.band78.nsa_2x2.106PRB.usrpn310.conf

ci-scripts/conf_files/gnb.band78.tm1.106PRB.usrpn300.conf

ci-scripts/ran.py

ci-scripts/xml_files/gnb_usrp_build.xml

cmake_targets/CMakeLists.txt

cmake_targets/build_oai

cmake_targets/install_external_packages.ubuntu20

cmake_targets/tools/build_helper

common/utils/system.c

doc/BUILD.md

docker/Dockerfile.eNB.rhel8.2

docker/Dockerfile.eNB.ubuntu18

docker/Dockerfile.gNB.rhel8.2

docker/Dockerfile.gNB.ubuntu18

docker/Dockerfile.lteUE.rhel8.2

docker/Dockerfile.lteUE.ubuntu18