Merge branch 't/btr_improvements'

	146316 btr_exec_up(): Also ask given node.
	6d9c35 btr: Introduce btr_add_output_dont_free().
	4ac313 btr: Remove btr_free_node().

Has been cooking in next for a week.

diff --cc NEWS
index 7fcf7f974a402907019cd0f0805a666cee3b603c,d38b977c60dcb73cc32370177dddd20b50c9cd6e..8f1b91da487d945548b1a8cb16fea0e07f6f40d6
--- 1/NEWS
--- 2/NEWS
+++ b/NEWS
@@@ -2,16 -2,14 +2,24 @@@
  0.4.11 (to be announced) "mutual diversity"
  -------------------------------------------
  
++The major feature in this release is the new sideband API for
++client-server communication. This API will be used exclusively starting
++with 0.5.0, which breaks backward compatibility but allows to get rid
++of quite some compatibility code. Other noteworthy changes include
++decoder latency improvements and a long-standing bug fix for the
++ALSA writer.
++
        - Sideband connections: If both para_server and para_client
          support this feature, data is sent as a multiplexed stream.
        - The --no_default_filters option of para_filter has been
          removed.
        - Several fixes and latency improvements to various decoders.
--      - The alsa writer now limits the prebuffer time to 500ms.
++      - The ALSA writer now limits the prebuffer time to 500ms.
        - Documentation improvements.
        - Overhaul of the command_util.sh script.
 +      - Fixes for some minor problems found by the clang analyzer.
 +      - Compiles (almost) without warnings on gcc-3.
++      - Robustness improvements of the buffer tree code.
  
  ------------------------------------------
  0.4.10 (2012-03-30) "heterogeneous vacuum"

diff --cc alsa_write.c
Simple merge

diff --cc buffer_tree.h
Simple merge

diff --cc client.c
Simple merge

diff --cc mp3dec_filter.c
Simple merge

diff --cc wmadec_filter.c
Simple merge