Added unit tests. Meant to be run with nodeunit

test/ishr.c0.bc0

@@ -0,0 +1,24 @@
+C0 C0 FF EE       # magic number
+00 09             # version 4, arch = 1 (64 bits)
+
+00 00             # int pool count
+# int pool
+
+00 00             # string pool total size
+# string pool
+
+00 01             # function count
+# function_pool
+
+#<main>
+00 00             # number of arguments = 0
+00 00             # number of local variables = 0
+00 06             # code length = 6 bytes
+10 FF    # bipush -1       # -1
+10 01    # bipush 1        # 1
+7A       # ishr            # (-(1) >> 1)
+B0       # return          # 
+
+00 00             # native count
+# native pool
+