Improve settings editor text (#79)

<!--- Provide a general summary of your changes in the Title above -->

## Description
<!--- Describe your changes in detail -->
Until settings editor is able to change settings, tell users what to do.

## Motivation and Context
<!--- What does this sample do? What problem does it solve? -->
<!--- If it fixes/closes/resolves an open issue, please link to the
issue here -->
Improve user experience.

## How Has This Been Tested?
<!-- (if applicable) -->
<!--- Please describe in detail how you tested your sample/changes. -->
<!--- Include details of your testing environment, and the tests you ran
to -->
<!--- see how your change affects other areas of the code, etc. -->
Tested locally.

## Screenshots
<!-- (if appropriate): -->

## Types of changes
<!--- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Improvement (non-breaking change that adds a new feature)
- [ ] Bug fix (fixes an issue)
- [ ] Breaking change (breaking change)
- [ ] Config and build (change in the configuration and build system,
has no impact on code or features)

## Checklist:
<!--- Go over all the following points, and put an `x` in all the boxes
that apply. -->
<!--- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
- [ ] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.

<!--- It would be nice if you could sign off your contribution by
replacing the name with your GitHub user name and GitHub email contact.
-->
Signed-off-by: GITHUB_USER <GITHUB_USER_EMAIL>

src/menu/views/settings_editor.c

@@ -31,6 +31,8 @@ static void draw (menu_t *menu, surface_t *d) {
         ALIGN_LEFT, VALIGN_TOP,
         "\n"
         "\n"
+        "To change the settings, please adjust them\n"
+        "directly in the 'menu/config.ini' file.\n\n"
         "pal60_enabled:         %s\n"
         "hidden_files_enabled:  %s\n"
         "default_directory:     %s\n"