Add vendor files for go build

vendor/github.com/alecthomas/chroma/lexers/d/diff.go

@@ -0,0 +1,29 @@
+package d
+
+import (
+	. "github.com/alecthomas/chroma" // nolint
+	"github.com/alecthomas/chroma/lexers/internal"
+)
+
+// Diff lexer.
+var Diff = internal.Register(MustNewLexer(
+	&Config{
+		Name:      "Diff",
+		Aliases:   []string{"diff", "udiff"},
+		EnsureNL:  true,
+		Filenames: []string{"*.diff", "*.patch"},
+		MimeTypes: []string{"text/x-diff", "text/x-patch"},
+	},
+	Rules{
+		"root": {
+			{` .*\n`, Text, nil},
+			{`\+.*\n`, GenericInserted, nil},
+			{`-.*\n`, GenericDeleted, nil},
+			{`!.*\n`, GenericStrong, nil},
+			{`@.*\n`, GenericSubheading, nil},
+			{`([Ii]ndex|diff).*\n`, GenericHeading, nil},
+			{`=.*\n`, GenericHeading, nil},
+			{`.*\n`, Text, nil},
+		},
+	},
+))