New command: skim, for adjusting the amount in the cashbox

Generally intended for board members only, so not listed in "help".

lib/RevBank/Cart/Entry.pm

@@ -38,6 +38,8 @@ sub add_contra($self, $user, $amount, $description) {
     };
 
     $self->attribute('changed', 1);
+
+    return $self;  # for method chaining
 }
 
 sub has_attribute($self, $key) {

lib/RevBank/Users.pm

@@ -24,7 +24,7 @@ sub names() {
 }
 
 sub balance($username) {
-    return _read()->{ lc $username }->[1];
+    return RevBank::Amount->new_from_float( _read()->{ lc $username }->[1] );
 }
 
 sub since($username) {