Genealogy as a feature (#175)

Start our journey into turning GeneIT as afully featured family intranet by making genealogy a feature that can be disabled by family admins

Reviewed-on: #175

geneit_backend/src/models.rs

@@ -65,6 +65,7 @@ pub struct Family {
     pub name: String,
     pub invitation_code: String,
     pub disable_couple_photos: bool,
+    pub enable_genealogy: bool,
 }
 
 impl Family {