Cleaning up lib-src

FileDialog goes into audacity/src/widgets and the mod-* directories go into
audacity/modules.

This leaves nothing in lib-src that isn't a 3rd-party libs or supporting
files.

modules/mod-nyq-bench/images/edit-undo-small.xpm

@@ -0,0 +1,83 @@
+/* XPM */
+static const char *edit_undo_small[] = {
+/* columns rows colors chars-per-pixel */
+"16 16 61 1",
+"  c #BB9F15",
+". c #BEA113",
+"X c #BCA114",
+"o c #BCA015",
+"O c #BDA116",
+"+ c #BBA11B",
+"@ c #BFA31B",
+"# c #C4A000",
+"$ c #C4A901",
+"% c #C8AC02",
+"& c #CBAA0E",
+"* c #C2A211",
+"= c #C1A313",
+"- c #C2A611",
+"; c #C1A314",
+": c #C1A319",
+"> c #C0A41A",
+", c #C5AB1B",
+"< c #C0A623",
+"1 c #D6C004",
+"2 c #DAC304",
+"3 c #D8C207",
+"4 c #DFC80A",
+"5 c #DFC80B",
+"6 c #DFC90F",
+"7 c #F7DD05",
+"8 c #E3CD16",
+"9 c #E8D21D",
+"0 c #F1DB29",
+"q c #F4DF2C",
+"w c #ECD936",
+"e c #FAE320",
+"r c #FBE425",
+"t c #F5E02F",
+"y c #F6E02F",
+"u c #F6E131",
+"i c #F7E232",
+"p c #F8E232",
+"a c #D8C543",
+"s c #DBC443",
+"d c #E1CD40",
+"f c #E3CE41",
+"g c #E9DA5D",
+"h c #EADB66",
+"j c #EBDC6F",
+"k c #EEE16E",
+"l c #F2E469",
+"z c #F3E56A",
+"x c #F6E769",
+"c c #F5E66D",
+"v c #F7E86C",
+"b c #F7E86E",
+"n c #F9EA69",
+"m c #FAEB6F",
+"M c #EFE276",
+"N c #FAEC73",
+"B c #FBED76",
+"V c #FBED79",
+"C c #F2E788",
+"Z c #FBF3AD",
+"A c None",
+/* pixels */
+"AAAAAA#AAAAAAAAA",
+"AAAAA##AAAAAAAAA",
+"AAAA#Z#AAAAAAAAA",
+"AAA#Zr##.o+AAAAA",
+"AA#ZueNmbno;AAAA",
+"A#Zyu0y08wxf=AAA",
+"#Zyppuy0999wdoAA",
+"A#Vpy1119995z,oA",
+"AA#B2Bnnnn741j@A",
+"AAA#BB####$M5z>A",
+"AAAA#B#AAAA#cM>A",
+"AAAAA##AAAAA%C=A",
+"AAAAAA#AAAAA&g<A",
+"AAAAAAAAAAAAsaAA",
+"AAAAAAAAAAAAh-AA",
+"AAAAAAAAAAAAAAAA"
+};