config: declare i outside for loop
zrtp: persistent ZID (thanks Ingo Feinerer)

the patch was contributed by Ingo Feinerer, thanks!

- add support for generating a random ZID the first time
  the application is started, and saving the ZID in
  $HOME/.baresip/zrtp_zid

- subsequent runs will read the ZID from this file

- setting client_id to "baresip/zrtp"

- setting license-mode to UNLIMITED
zrtp: send control packets from this UDP-helper

- udp_send() will process *all* send helpers on that UDP-socket, from
  the top-level helper to the bottom-level helper (including the
  helper used by zrtp).

- instead we use udp_send_helper() which will send the outgoing packet
  from the helper right *below* this helper (st->uh), and continue down
  the chain of helpers.

- the logic behind UDP-helpers is that a particular helper should not
  know about any other potential helpers above or below
avcodec: use codecid with AV_ prefix

- use enum AVCodecID instead of enum CodecID
- use AV_CODEC_ID_xxx instead of CODEC_ID_xxx
- extend a backwards compatible macro-wrapper in
  avcodec.h

avcodec should still compile on old versions of FFmpeg.
please let us know if it does not :)
avformat: dont use deprecated symbols
vidloop: print framerate
v4l2: remove support for read, only use MMAP

- also minor cleanups
config: generate more relevant config for FreeBSD and OpenBSD
Merge pull request #20 from czarkoff/openbsd

config: generate more relevant config for FreeBSD and OpenBSD
vumeter: call tmr_start() from re_main thread

- tmr_start() should not be called from a thread that is not running
  the re_main() loop. i.e. tmr_start() MUST be called from the re_main()
  loop thread, unless the call is wrapped by re_thread_enter/leave().

- the audio-processing handlers encode/decode are handling real-time
  audio samples, and should not be blocked.
zrtp: add support for SAS verification

- the patch was contributed by Ingo Feinerer

- use the command 'Z' to write verified ZID
zrtp: set cache type to file

contributed by Ingo Feinerer, thanks !
zrtp: print Z-command info
modules/presence: allow notify without body
metric: add metric_init()

- metric_init calls tmr_start(). tmr_start must be called from the
  re_main() thread.
modules/mwi: subscribe to mwi after registration has succeeded
fix whitespace, use TAB for indentation

the python-program ccheck.py can be used to verify that the source
code does not contain any whitespace errors:

  https://github.com/alfredh/pytools/blob/master/ccheck.py

how to use it:

  $ cd baresip
  $ ccheck.py
gruu: preliminary support for SIP GRUU

- the original patch was written by Juha Heinanen

- this patch needs a new version of libre
fix warnings on Mac OSX
ui: update UI-module API

- change from multiple-instances to single-instance
  (multiple-instances was never used)

- remove ui/input config parameters from the "core" config,
  moved to each specific module (cons and evdev)

- modules updated: stdio, cons, evdev, wincons

- this patch solves the reported crash, that module-functions
  are called after the module was unloaded.