Add some example scripts for pyboard (some can run on PC).

examples/pyb.py

@@ -0,0 +1,11 @@
+# pyboard testing functions for PC
+
+def delay(n):
+    pass
+
+rand_seed = 1
+def rand():
+    global rand_seed
+    # for these choice of numbers, see P L'Ecuyer, "Tables of linear congruential generators of different sizes and good lattice structure"
+    rand_seed = (rand_seed * 653276) % 8388593
+    return rand_seed