Added modules for test points and solder pads. Some cleanup.

- AUTHORS, modules/INFO, modules/Makefile, modules/pads.fpd: added pads
- modules/Makefile: added forgotten "qfn" module
- modules/xtal-4.fpd: renamed crystal module from xtal-4-* to xtal4-*, for
  clarity

modules/pads.fpd

@@ -0,0 +1,18 @@
+/* MACHINE-GENERATED ! */
+
+frame pad {
+	__0: vec @(x/2, y/2)
+	__1: vec @(-x/2, -y/2)
+	rpad "1" . __0
+}
+
+package "PAD_$name"
+unit mm
+
+table
+    { name, x, y }
+    { "2mm", 2mm, 0.5mm }
+    { "60x60", 60mil, 60mil }
+    { "120x60", 120mil, 60mil }
+
+frame pad @