Fixed some more issues for running with multiple UEs. Added configuration option for the number of UEs.

Minor modifications. Some problem appears rarely that prevents the reception of RRCConnectionSetupComplete message at the eNB.

making oaisim_nos1 compile

basically the T_xx variables are int, not uint

phy_init_lte_ue_signal was renamed init_lte_ue_signal in openair1/PHY/INIT/defs.h
maybe it's the opposite that should have been done?

Functions used in one file and defined in another may have been
declared in the wrong header file.

Improve configuration module error management at init time, Fix command line help option processing, remove shotopt field from parameter structure

lte-softmodem -O <config file> will trigger legacy config mode
ltesoftmodem  -O libconfig:<config file> will trigger configuration module usage.

- some cleanup
- thread names to include UE Mod_id
- arg of UE_thread_rxn_txnp4 to be struct rx_tx_thread_data again
- sync in UE_thread_rxn_txnp4 to use instance_cnt_rxtx again
- UE_thread to call itti_send_msg_to_task with UE->Mod_id + NB_eNB_INST
  instead of INSTANCE_DEFAULT again

This may break the softmodem UE, to be tested.
The most problematic thing may be the synchronization.
I don't think it will impact the processing at all,
but I won't bet my shirt on it.