AddressBook: make sort case insensitive.

Fixes #34.

src/components/AddressBook.tsx

@@ -65,13 +65,7 @@ const sortSelector = createSelector(
       const a = _a.fn;
       const b = _b.fn;
 
-      if (a < b) {
-        return -1;
-      } else if (a > b) {
-        return 1;
-      } else {
-        return 0;
-      }
+      return a.localeCompare(b, undefined, {sensitivity: 'base'});
     });
   }
 );