[ANNOUNCE] VDR developer version 2.1.1

- Removed all "modified since version 1.6" markers from PLUGINS.html.
- Changed the sign of the satellite position value in cSource to reflect the standard
  of western values being negative. The new member function cSource::Position() can be
  used to retrieve the orbital position of a satellite.
- Added basic support for positioners to control steerable satellite dishes (based on
  a patch from Seppo Ingalsuo and Ales Jurik).
  + Supports GotoN (aka "DiSEqC 1.2") and GotoX (aka "USALS").
  + The new DiSEqC command code 'P' can be used to instruct a positioner to move the
    dish to the required satellite position. When a 'P' code is processed, further
    execution of the remaining DiSEqC sequence (if any) is postponed until the positioner
    has reached the new satellite position.
  + The new special source value of "S360E" can be used in diseqc.conf to indicate that
    an entry using a positioner can move the dish to any requested position within its
    range. Think of it as "full circle".
  + The devices a particular cDiseqc or cScr applies to are now stored directly in each
    cDiseqc or cScr, respectively.
  + A plugin can implement a custom positioner control (see PLUGINS.html, section "Positioners").
  + The new function cSkinDisplayChannel::SetPositioner() can be implemented by skins to
    show the user a progress display when the dish is being moved. The default implementation
    calls SetMessage() with a string indicating the new position the dish is being moved to.
    The LCARS skin shows a progress bar indicating the movement of the dish.
  + The new parameters "Site latitude", "Site longitude", "Positioner speed", and
    "Positioner swing" in the "Setup/LNB" menu can be used to configure the necessary
    values for a steerable dish.
  + The cDvbTuner now has a new status tsPositioning, in which it waits until a steerable
    dish has reached its target position. Parsing SI data is paused until the target
    position has been reached.
- The LCARS skin now shows the source value of the current channel in its channel display.
- Reverted the change from version 1.5.7 that made all logging go to LOG_ERR (thanks
  to Christopher Reimer).
- Added Begin/EndSegmentTransfer() to the EPG handler interface (thanks to Jörg Wendel).
- The code for distributing recordings over several video directories is now
  deprecated and disabled by default.
  You can re-enable this feature by removing the comment sign ('//') from the beginning
  of the line
  //#define DEPRECATED_DISTRIBUTED_VIDEODIR // Code enclosed with this macro is ...
  in the file videodir.c. Note, though, that this can only be a temporary workaround.
  This feature will be completely removed in one of the next developer versions.
  Distributing the video directory over several disks was a useful feature in times
  when disks were still relatively small, but it also caused serious problems in case
  one of the disks failed. Nowadays hard disks come in sizes measured in terabytes,
  and tools like "mhddfs" can be used to combine several disks to form one large volume.
  A recommended method for a relatively safe disk setup in a VDR system is to use two
  1TB (or larger) disks and use them as a RAID-1 (mirrored). That way, if one disk
  fails, you can replace it without data loss.