fixed compilatiaon issues after merge with develop and enhancement-rfsim. Intitial testing with emulator.

Conflicts:
	cmake_targets/build_oai
	openair1/PHY/LTE_ESTIMATION/lte_sync_time.c
	openair1/PHY/LTE_TRANSPORT/dci_tools.c
	openair1/PHY/LTE_TRANSPORT/if4_tools.c
	openair1/PHY/LTE_TRANSPORT/prach.c
	openair1/PHY/defs_eNB.h
	openair1/PHY/impl_defs_lte.h
	openair2/ENB_APP/enb_config.c
	openair2/LAYER2/MAC/eNB_scheduler.c
	openair2/LAYER2/MAC/eNB_scheduler_ulsch.c
	targets/RT/USER/lte-enb.c
	targets/RT/USER/lte-ru.c
	targets/SIMU/USER/channel_sim.c
	targets/SIMU/USER/oaisim.c
	targets/SIMU/USER/oaisim_config.c
	targets/SIMU/USER/oaisim_functions.c

Merge branch 'ru_rau_enhancement' of http://gitlab.eurecom.fr/oai/openairinterface5g into ru_rau_enhancement

Conflicts:
	targets/RT/USER/lte-ru.c

Merge branch 'enhancement-rfsim' of https://gitlab.eurecom.fr/oai/openairinterface5g into enhancement-rfsim

Conflicts:
	targets/RT/USER/lte-uesoftmodem.c

moved sidlink L1 functions to LTE_UE_TRANSPORT, corrected issue related to "find_dlsch" which is needed to compile UE and creates problem for unitary simulations (moved to lte-ue.c application)

Summary of changes:
- split UE and eNB directories
- nFAPI L2 emulator
- basic simulator
- various bug fixes

The nFAPI L2 emulator is not functional yet. Some code had to be removed
because it made the monolithic eNB non functional.

The unitary simulators (ulsim, dlsim) do not compile anymore. This will
be fixed later.

Remove warnings found while running:
    ./build_oai --UE -c -w USRP

And:
    ./build_oai --basic-simulator -c

Remove warnings popping up on:
    ./build_oai --eNB -w USRP

Maybe not always the best solution.

MAX_MOBILES_PER_ENB cannot be used to compile ue_ip
because it is defined in platform_constants.h and this
cannot be included to compile a kernel module.

Let's use NUMBER_OF_UE_MAX as it was before instead.

Merge remote-tracking branch 'origin/feature-better-sw-configuration-between-various-version' into develop_integration_2018_w19

Conflicts:
	cmake_targets/CMakeLists.txt
	openair1/PHY/LTE_TRANSPORT/prach.c
	openair1/PHY/LTE_TRANSPORT/print_stats.c
	openair1/PHY/LTE_TRANSPORT/transport_eNB.h
	openair1/PHY/LTE_UE_TRANSPORT/transport_proto_ue.h
	openair1/PHY/defs_eNB.h
	openair1/PHY/impl_defs_lte.h
	openair1/SCHED/sched_common.h
	openair1/SCHED_UE/phy_procedures_lte_ue.c
	openair2/LAYER2/MAC/mac.h
	openair2/LAYER2/PDCP_v10.1.0/pdcp.c
	openair2/LAYER2/PDCP_v10.1.0/pdcp.h
	openair2/LAYER2/PDCP_v10.1.0/pdcp_fifo.c
	openair2/LAYER2/RLC/rlc.c
	openair2/PHY_INTERFACE/defs.h
	openair2/RRC/LTE/MESSAGES/asn1_msg.c
	openair2/RRC/LTE/MESSAGES/asn1_msg.h
	openair2/RRC/LTE/rrc_UE.c
	openair2/RRC/LTE/rrc_eNB.c
	targets/SIMU/USER/oaisim_functions.c

Merge remote-tracking branch 'origin/feature-ubuntu-18.04-build-usrp' into develop_integration_2018_w19

Merge remote-tracking branch 'origin/bugfix-add-error-indication-handling' into develop_integration_2018_w19

The new 'basic simulator' is now functional.
A proper solution is needed to deal with SIB18/19/21
for the D2D functionality.

This is a quick and dirty solution, something better is needed.