Merge branch 'develop_integration_w48' into 'develop'

Develop integration 2018 week 48

See merge request oai/openairinterface5g!462

Integration of the following MRs:

 - MR 448: Missing RRC inactivity timer
 - MR 458: Adding MAC main config to RRC connection setup
 - MR 457: Resolving "parallelization not working correctly in phy simulators"
 - MR 460: Fixing RU DFT initialization