This commit fixes issues introduced by the previous commit.

Summary of work:
- cleanup:
  - fix LOG_XX to be less verbose
  - fix cmake_targets/CMakeLists.txt
  - fix oaienv
  - remove dead code
- bug fixes:
  - in openair1/SCHED/fapi_l1.c we had:
      eNB->pdcch_vars[subframe&1].num_dci           = number_dci;
    should be:
      eNB->pdcch_vars[subframe&1].num_dci           = 0;
    This bug let the PHY send more DCIs than what should have been
    sent because num_dci is incremented later on in the code.
    This fix may be a problem for fapi mode, to be checked.
  - add new T VCD traces
  - revert openair1/PHY/TOOLS/file_output.c to 'develop' version
  - remove thread_id in logRecord/logRecord_mt
  - revert (and adapt) configuration files
  - be careful when doing frame++, we need to % 1024
  - revert target_rx_power in openair2/LAYER2/MAC/eNB_scheduler_ulsch.c
- NFAPI:
  - the open-nFAPI code has been included in the repository. See nfapi/README.
    Maybe we should "git clone" the Cisco repository instead. We have to be
    careful of availability though.

What has been tested:
- monolithic eNB FDD 5/10MHz with one UE, iperf UDP/TCP uplink/downlink

Anything else may fail to work, especially the FAPI mode, which has not
been tested at all.

Sometimes when the user does ctrl+c to quit, it may not quit
if nothing comes on the socket. Closing the socket in the
signal handler fixes this.

Do not link the X stuff for tracers not needing it.

Later on, use this file with gtkwave.
To be used to check realtime behaviour of the system.

This tracer extracts output subframes generated by the eNodeB,
so they can be analyzed with some external tools.

This tracer extracts the content of a buffer field of an event
that was previously saved using the tracer 'record'.

For example, to extract the channel estimation done in
frame 924 and subframe 2 as saved in the file input_record.raw
and to store it in the file output.raw, do:

./extract -d ../T_messages.txt -o output.raw input_record.raw ENB_PHY_UL_CHANNEL_ESTIMATE chest_t -f frame 924 -f subframe 2

- UE_id 0 is for rnti 65535 (sib)
- UE_id 1 is for rnti 65534 (this is a hack)
- UE_id 2 is for rnti 2     (RA RNTI as of today's code/config)
- we start enb by displaying UE_id 3
- there was a bug: we need to lock when resetting UE ids (reset_ue_ids)

not finished, UE may not work, many things bad/to fix properly

- ENB_PHY_OUTPUT_SIGNAL to trace output signal
- ENB_MAC_SCHEDULING_REQUEST to trace scheduling requests

This program extracts a given subframe from a recorded trace.

We now have 4 versions of T_HEADER:
 - bad quality C++ version with time
 - good quality C version with time
 - bad quality C++ version without time
 - good quality C version without time

we want those traces in the logs people send to us and
the group HEAVY is disabled in the wiki instructions.

looks better

Normally it is used to display throughput.

The computation it does is to sum up the wanted value for the last
second (1000 TTIs) and send this value to the views associated to
this logger, at each TTI.

This view is used to display throughput (to come in next commits).

- change paint function:
  when the XY plot is resized we scale. Previously
  the last range was put in the middle of the new range
  (say when we increase the size).
  We may get aspect ratio changes if the resize is not identical
  vertically and horizontally, but I think this behaviour is more
  'natural'.
- fix a bug:
  the last horizontal tick label was printed to far on the right,
  out of the bouding box of the XY plot. This is not totally fixed
  in the case the label is larger than the XY plot. Now the part
  out of the bounding box will be printed on the left. No big deal,
  make the plot big enough. (Before, even if big enough you had a
  problem.)
- add a new vertical tick display, to be used for throughput mostly.
  See in enb.c the difference between 'input signal' and throughput
  plots (those throughput plots will come in later commits).

It's like a label but with fixed dimensions and maximum
characters' capacity at creation time.

This function is used to print rates (say '1kb/s' or '16Mb/s').