Interrupt system implemented, some new programs.

Programs/testPrograms/diagnostics/duplicateVector.asm

@@ -0,0 +1,20 @@
+; Two handlers claiming the same vector.
+;
+; Device lines name a port directly, so two of them can collide even though the
+; assembler numbers the named vectors itself.
+
+#Program
+
+start:
+  HALT
+
+firstHandler:
+  RETI
+
+secondHandler:
+  RETI
+
+#Vectors
+
+  Device 0x10  firstHandler
+  Device 0x10  secondHandler