Re-organize the example programs.

eg/c64/screen2.60p

@@ -1,7 +1,7 @@
 // Displays 256 hearts at the top of the Commodore 64's screen.
 
 // Define where the screen starts in memory:
-byte table screen @ 1024
+byte table[256] screen @ 1024
 
 routine main
   // These are the values that will be written to by this routine:

eg/rudiments/README.md

@@ -0,0 +1,9 @@
+This directory contains example sources which demonstrate
+the rudiments of SixtyPical.
+
+Some are meant to fail and produce an error message.
+
+They are not meant to be specific to any architecture, but
+many do assume the existence of a routine at 65490 which
+outputs the value of the accumulator as an ASCII character,
+simply for the purposes of producing some observable output.

eg/rudiments/range-error.60p

@@ -0,0 +1,9 @@
+byte table[8] message : "WHAT?"
+
+routine main
+  inputs message
+  outputs x, a, z, n
+{
+  ld x, 9
+  ld a, message + x
+}