Implemented all four primary half-word moves (HLL, HLR, HRL, HRR) but none of the flavors (Z, O, E); need to test the primary instructions first

apps/pdp10/tests/optest.json

@@ -2,6 +2,6 @@
   "load": 0o100,
   "exec": 0o100,
   "data": [
-    0o500000000000
+    0o505040111111,   // HRLI  1,111111
   ]
 }