parser: revision 1 done; super dirty

examples/factorial

@@ -0,0 +1,20 @@
+ENTRY 22
+LOAD -3
+CONST 2
+LT
+BRF 10
+CONST 1
+RET
+LOAD -3
+LOAD -3
+CONST 1
+SUB
+CALL 0 1
+MULT
+RET
+CONST 12
+CALL 0 1
+IPRINT
+CONST 10
+PRINT
+HALT