Add call trace test for transfer precompile

This test exercises both the call tracer and the transfer precompile. It
is the first test that checks for the gas cost and return value of the
precompile.

See #69

eth/tracers/internal/tracetest/testdata/call_tracer/transfer_precompile.json

@@ -62,7 +62,7 @@
   "result": {
     "from": "0x42cf1bbc38baaa3c4898ce8790e21ed2738c6a4a",
     "gas": "0x857e",
-    "gasUsed": "0x8418",
+    "gasUsed": "0x83c9",
     "to": "0x471ece3750da237f93b8e339c536989b8978a438",
     "input": "0xa9059cbb000000000000000000000000000000000000000000000000000000000000dead0000000000000000000000000000000000000000000000000000000000000064",
     "output": "0x0000000000000000000000000000000000000000000000000000000000000001",
@@ -73,7 +73,6 @@
         "gasUsed": "0x2328",
         "to": "0x00000000000000000000000000000000000000fd",
         "input": "0x00000000000000000000000042cf1bbc38baaa3c4898ce8790e21ed2738c6a4a000000000000000000000000000000000000000000000000000000000000dead0000000000000000000000000000000000000000000000000000000000000064",
-        "output": "0x00000000000000000000000042cf1bbc38baaa3c4898ce8790e21ed2738c6a4a000000000000000000000000000000000000000000000000000000000000dead0000000000000000000000000000000000000000000000000000000000000064",
         "value": "0x0",
         "type": "CALL"
       }