Merge branch 'refs/heads/t/image_id_mm'

A single commit that was cooking for several months.

* refs/heads/t/image_id_mm:
  server: Add mood methods image_id and lyrics_id.

diff --combined NEWS
index a5bef9f633eb8f25319865ea48f79bd8e34785a6,7faa0dddfd6c08954a03b3ef79d768dc14014d6e..1481f687406a654928adfe9aba85777953770c9f
--- 1/NEWS
--- 2/NEWS
+++ b/NEWS
@@@ -5,14 -5,13 +5,19 @@@ NEW
  current master branch "cascading gradient"
  ------------------------------------------
  
++The highlight of this release is the new -m flag for para_afh which
++lets it modify the meta tags of the given audio file(s). This feature
++is supported for all audio formats. Many small cleanups and bug fixes
++not mentioned here have accumulated and are also part of the release.
++
        - para_afh learned to modify meta tags of mp3 wma ogg spx
          opus flac aac files.
        - afs commands propagate error codes to the client.
        - The check command now also checks the attribute table for
          inconsistencies.
        - New -v flag for the version command (print verbose version string)
 -
 +      - New option --priority for para_server and para_audiod.
- 
++      - New mood methods: image_id and lyrics_id.
  
  --------------------------------------
  0.5.5 (2015-09-20) "magnetic momentum"

diff --combined web/manual.m4
index d63b07e8cbb69067439db6bca4875f9867908831,88e31169325daae526a09087b834e9bc5a3646a3..59abc5385f9eb5cdcc4a21bfbdb6a30567fa6b90
--- 1/web/manual.m4
--- 2/web/manual.m4
+++ b/web/manual.m4
@@@ -956,12 -956,13 +956,13 @@@ is not set, the empty string is matche
        frequency ~ <num>
        channels ~ <num>
        num_played ~ <num>
+       image_id ~ <num>
+       lyrics_id ~ <num>
  
  Takes a comparator ~ of the set {<, =, <=, >, >=, !=} and a number
  <num>. Matches an audio file iff the condition <val> ~ <num> is
  satisfied where val is the corresponding value of the audio file
- (value of the year tag, bitrate in kbit/s, frequency in Hz, channel
- count, play count).
+ (value of the year tag, bitrate in kbit/s, etc.).
  
  The year tag is special as its value is undefined if the audio file
  has no year tag or the content of the year tag is not a number. Such
@@@ -2010,19 -2011,21 +2011,19 @@@ Doxyge
  ~~~~~~~
  
  Doxygen is a documentation system for various programming
 -languages. The paraslash project uses Doxygen for generating the API
 -reference on the web pages, but good source code documentation is
 -also beneficial to people trying to understand the code structure
 -and the interactions between the various source files.
 +languages. The API reference on the paraslash web page is generated
 +by doxygen.
  
  It is more illustrative to look at the source code for examples than
 -to describe the conventions for documenting the source in this manual,
 -so we only describe which parts of the code need doxygen comments,
 -but leave out details on documentation conventions.
 +to describe the conventions in this manual, so we only describe which
 +parts of the code need doxygen comments, but leave out details on
 +documentation conventions.
  
  As a rule, only the public part of the C source is documented with
  Doxygen. This includes structures, defines and enumerations in header
  files as well as public (non-static) C functions.  These should be
 -documented completely. For example each parameter and the return
 -value of a public function should get a descriptive comment.
 +documented completely. For example, each parameter and the return
 +value of a public function should get a descriptive doxygen comment.
  
  No doxygen comments are necessary for static functions and for
  structures and enumerations in C files (which are used only within