use $EDITOR, default to vim, use $HOME/.vimrc if exists

cmd/pttodo-cli/cli.go

@@ -61,13 +61,25 @@ func edit(dry bool, filepath string) error {
 		return nil
 	}
 	vi := func() error {
-		vibin, err := exec.LookPath("vi")
+		bin := "vim"
+		if editor := os.Getenv("EDITOR"); editor != "" {
+			bin = editor
+		}
+		editorbin, err := exec.LookPath(bin)
+		if err != nil {
+			editorbin, err = exec.LookPath("vi")
+		}
 		if err != nil {
 			return err
 		}
+		args := []string{editorbin, tempFile}
+		vimrc := path.Join(os.Getenv("HOME"), ".vimrc")
+		if _, err := os.Stat(vimrc); err == nil {
+			args = append(args, "-u", vimrc)
+		}
 		cpid, err := syscall.ForkExec(
-			vibin,
-			[]string{vibin, tempFile},
+			editorbin,
+			args,
 			&syscall.ProcAttr{
 				Dir:   "",
 				Env:   os.Environ(),