clean up various TODOs and comments

generate/template.go

@@ -7,8 +7,11 @@ import (
 )
 
 // TODO: package templates into the binary using one of those asset thingies
-var _, thisFilename, _, _ = runtime.Caller(0)
-var thisDir = filepath.Dir(thisFilename)
+// (e.g. embed, if we wait until 1.16 to do this)
+var (
+	_, thisFilename, _, _ = runtime.Caller(0)
+	thisDir               = filepath.Dir(thisFilename)
+)
 
 func mustTemplate(relFilename string) *template.Template {
 	return template.Must(template.ParseFiles(filepath.Join(thisDir, relFilename)))