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/media-playback-pause-small.xpm

@@ -0,0 +1,65 @@
+/* XPM */
+static const char *media_playback_pause_small[] = {
+/* columns rows colors chars-per-pixel */
+"16 16 43 1",
+"  c #555753",
+". c #595B57",
+"X c #5C5E5A",
+"o c #5F615D",
+"O c #5F625D",
+"+ c #626460",
+"@ c #626560",
+"# c #656763",
+"$ c #666863",
+"% c #696B66",
+"& c #696B67",
+"* c #6C6E69",
+"= c #6C6E6A",
+"- c #6F716C",
+"; c #70736E",
+": c #72746F",
+"> c #737570",
+", c #D6DAD2",
+"< c #D8DBD5",
+"1 c #D9DDD6",
+"2 c #DCDFD8",
+"3 c #DDDFDA",
+"4 c #DFE2DC",
+"5 c #E0E3DD",
+"6 c #E1E3DE",
+"7 c #E1E4DF",
+"8 c #E4E5E2",
+"9 c #E4E6E2",
+"0 c #E5E8E4",
+"q c #E9EBE7",
+"w c #ECEDEB",
+"e c #EEEFEC",
+"r c #EFF0ED",
+"t c #F0F1EF",
+"y c #F1F3F0",
+"u c #F3F3F3",
+"i c #F3F4F2",
+"p c #F4F5F3",
+"a c #F7F8F7",
+"s c gray99",
+"d c #FCFDFC",
+"f c gray100",
+"g c None",
+/* pixels */
+"gggggggggggggggg",
+"gggggggggggggggg",
+"gggggggggggggggg",
+"ggg    gg    ggg",
+"ggg.ff.gg.ff.ggg",
+"gggXf<XggXf,Xggg",
+"gggoy3oggop1oggg",
+"ggg+w4+gg+r7+ggg",
+"ggg#06#gg$eq#ggg",
+"ggg%94&gg%ry%ggg",
+"ggg*93*gg*ya*ggg",
+"ggg-sf;gg-ff;ggg",
+"ggg:>>>gg>>>>ggg",
+"gggggggggggggggg",
+"gggggggggggggggg",
+"gggggggggggggggg"
+};