Add Commercial Instruction Set.

I haven't done much compatibility testing with MACRO11 to check
weirdnesses, but the original functionality is very limied: none
of the mnemonics has operands.

tests/RunTests

@@ -10,6 +10,7 @@ TESTS="test-asciz \
     test-backpatch \
     test-blkb \
     test-bsl-mac-arg \
+    test-cis \
     test-complex-reloc \
     test-enabl-ama \
     test-enabl-lcm \