Introduce Golang-based benchmarking utility (#769)

* Introduce Golang-based benchmarking utility

* benchmark fio: properly configure logger level

* benchmark: properly terminate on Ctrl+C when initializing/running Tart

* benchmark(fio): increase runtime to 30 seconds

* benchmark(fio): IOPS are already per second

* benchmark(fio): --numjobs 1 --iodepth 1 --end_fsync 1

* benchmark(README.md): add results

benchmark/internal/command/root.go

@@ -0,0 +1,20 @@
+package command
+
+import (
+	"github.com/cirruslabs/tart/benchmark/internal/command/fio"
+	"github.com/spf13/cobra"
+)
+
+func NewCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:           "benchmark",
+		SilenceUsage:  true,
+		SilenceErrors: true,
+	}
+
+	cmd.AddCommand(
+		fio.NewCommand(),
+	)
+
+	return cmd
+}