Bring back the reverse flag

Following the large refactor on the previous commit, this commit fixes
the reverse functionality.

Depth detection moved into the tree building instead of being calculated
when drawing the tree to screen

src/utils/mod.rs

@@ -122,15 +122,6 @@ pub fn sort_by_size_first_name_second(a: &(String, u64), b: &(String, u64)) -> O
     }
 }
 
-pub fn compare_tuple_smallest_first(a: &(String, u64), b: &(String, u64)) -> Ordering {
-    let result = a.1.cmp(&b.1);
-    if result == Ordering::Equal {
-        b.0.cmp(&a.0)
-    } else {
-        result
-    }
-}
-
 pub fn sort(data: HashMap<String, u64>) -> Vec<(String, u64)> {
     let mut new_l: Vec<(String, u64)> = data.iter().map(|(a, b)| (a.clone(), *b)).collect();
     new_l.sort_by(|a, b| sort_by_size_first_name_second(&a, &b));