Benchmark against other libraries (#175)

BenchmarkUnmarshalToml-8             1000  1320117 ns/op  450932 B/op  15072 allocs/op
BenchmarkUnmarshalBurntSushiToml-8   3000   402897 ns/op   82900 B/op   1761 allocs/op
BenchmarkUnmarshalJson-8            20000    66092 ns/op    3536 B/op    101 allocs/op
BenchmarkUnmarshalYaml-8            10000   189600 ns/op   44872 B/op   1058 allocs/op

benchmark.sh

@@ -13,7 +13,7 @@ fi
 
 tempdir=`mktemp -d /tmp/go-toml-benchmark-XXXXXX`
 ref_tempdir="${tempdir}/ref"
-ref_benchmark="${ref_tempdir}/benchmark-${reference_ref}.txt"
+ref_benchmark="${ref_tempdir}/benchmark-`echo -n ${reference_ref}|tr -s '/' '-'`.txt"
 local_benchmark="`pwd`/benchmark-local.txt"
 
 echo "=== ${reference_ref} (${ref_tempdir})"
@@ -25,7 +25,7 @@ popd >/dev/null
 
 echo ""
 echo "=== local"
-go test -bench=. -benchmem | tee ${local_benchmark}
+go test -bench=. -benchmem  | tee ${local_benchmark}
 
 echo ""
 echo "=== diff"