preferences: update preferences categories and dependencies

GitLab: #16
Change-Id: Ib02e4201db803ea81abb305e00e494d46e837ad1
diff --git a/.gitignore b/.gitignore
index 1e8bf2c..01d29d3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,3 +8,6 @@
 *__pycache__*
 /foo/
 /.vscode/
+*.crt
+*.key
+*.sign