wave_encoder: new encoder for streaming PCM wave files.

When using wave encoder with httpd audio output mpd can input this stream via http and audiofile decoder.
This for example opens simple way to configure lossless audio streaming port(like jack or pulseaudio does but without overhead).
Another possibility can be using it for gathering raw data for visualization plugins (If sync issue will be resolved)

configure.ac

@@ -659,6 +659,11 @@ AC_ARG_ENABLE(twolame-encoder,
 		[enable the TwoLAME mp2 encoder]),,
 	enable_twolame_encoder=auto)
 
+AC_ARG_ENABLE(wave-encoder,
+	AS_HELP_STRING([--enable-wave-encoder],
+		[enable the PCM wave encoder]),,
+	enable_wave_encoder=yes)
+
 
 dnl
 dnl audio output plugins
@@ -1078,6 +1083,7 @@ else
 	enable_vorbis_encoder=no
 	enable_lame_encoder=no
 	enable_twolame_encoder=no
+	enable_wave_encoder=no
 fi
 
 MPD_AUTO_PKG(vorbis_encoder, VORBISENC, [vorbisenc],
@@ -1097,7 +1103,8 @@ MPD_AUTO_PKG(twolame_encoder, TWOLAME, [twolame],
 
 if test x$enable_vorbis_encoder != xno ||
 	test x$enable_lame_encoder != xno ||
-	test x$enable_twolame_encoder != xno; then
+	test x$enable_twolame_encoder != xno ||
+	test x$enable_wave_encoder != xno; then
 	# at least one encoder plugin is enabled
 	enable_encoder=yes
 else
@@ -1178,6 +1185,11 @@ if test x$enable_twolame_encoder = xyes; then
 		[Define to enable the TwoLAME encoder plugin])
 fi
 
+AM_CONDITIONAL(ENABLE_WAVE_ENCODER, test x$enable_wave_encoder = xyes)
+if test x$enable_wave_encoder = xyes; then
+	AC_DEFINE(ENABLE_WAVE_ENCODER, 1,
+		[Define to enable the PCM wave encoder plugin])
+fi
 
 dnl
 dnl Documentation
@@ -1429,6 +1441,12 @@ if
 			echo " TwoLAME mp3 encoder ...........disabled"
 		fi
 
+		if test x$enable_wave_encoder = xyes; then
+			echo " PCM wave encoder ..............enabled"
+		else
+			echo " PCM wave encoder ..............disabled"
+		fi
+
 		echo ""
 fi