Rewrite shell cmd parser

pkg/shell/shell_test.go

@@ -0,0 +1,18 @@
+package shell
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestQuoteSplit(t *testing.T) {
+	s := `
+python "-c" 'import time
+print("time", time.time())'
+`
+	require.Equal(t, []string{"python", "-c", "import time\nprint(\"time\", time.time())"}, QuoteSplit(s))
+
+	s = `ffmpeg -i video="0" -i "DeckLink SDI (2)"`
+	require.Equal(t, []string{"ffmpeg", "-i", "video=\"0\"", "-i", "DeckLink SDI (2)"}, QuoteSplit(s))
+}