[gnome-tweak-tool] README.md: Mention nautilus schemas runtime dependency

[Jeremy Bicha <jbicha src gnome org>]

commit 0c0ca08c6290d48a441db540a9d40338e16fafe8
Author: Jeremy Bicha <jbicha ubuntu com>
Date:   Sun Oct 8 16:34:24 2017 -0400

    README.md: Mention nautilus schemas runtime dependency
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788685

 README.md |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/README.md b/README.md
index 11ebade..1c095c5 100644
--- a/README.md
+++ b/README.md
@@ -28,6 +28,7 @@ RUNTIME DEPENDENCIES
   - gsettings-desktop-schemas (>= 3.24)
   - gnome-shell (>= 3.24)
   - mutter
+  - nautilus
 
 * Optional:
    - gnome-software (for links from GNOME Shell Extensions page)