changes:
- ue mcc/mnc 208.93
- use correct key/opc for user
- change addresses in conf file for them to be easier to understand
  (maybe)

With those changes, running:
   sudo ./run_enb_ue_virt_s1
in cmake_targets/tools should work out of the box

The user still has to configure correct IP addresses in
targets/PROJECTS/GENERIC-LTE-EPC/CONF/enb.band7.generic.oaisim.local_mme.conf

We supposed oaisim (enb+ue) machine to be on IP address 10.0.1.1
and EPC (hss, mme, spgw) machine to be on IP address 10.0.1.2.

Keys/IDs have been inadvertently changed.

- fix OPc key
- clear EHPLMN_LIST, UE does not start the RA procedure when set
  to be fixed

This patch adds the conf2uedata tool for generating .ue.nvram* .ue.emm.nvram*
and .usim.nvram* files from a textual configuration file.

The configuration file define most usefull values like plmns, mnc, mcc, msin, K,
OPc for several users.
The files generated will always ends with a number corresponding to the user
entry in the configuration file.

This breaks oai5g because other script have not be updated for using
conf2uedata.
This breaks also the at_nas_ue command.

Examples of configuration files are in openair3/NAS/TOOLS/