fix indentation to two spaces

Author: svenwey

app/views/plannings/base/_header_planned.html.haml

@@ -4,18 +4,18 @@
 -#  https://github.com/puzzle/puzzletime.
 
 .header-planned-container
-    .header-planned-row.total-sum
-        .header-planned-prefix 
-            Total:
-        .header-planned-amount
-            = format_number(@board.total_planned_hours, 0) + ' / ' + format_number(@board.total_plannable_hours, 0)
-        .header-planned-postfix 
-            Stunden verplant
-    .header-planned-row.inperiod-sum
-        .header-planned-prefix 
-            Ausgewählter Zeitbereich:
-        .header-planned-amount
-            = format_number(@board.total_planned_hours(true), 0)
-        .header-planned-postfix 
-            Stunden verplant
+  .header-planned-row.total-sum
+    .header-planned-prefix 
+      Total:
+    .header-planned-amount
+      = format_number(@board.total_planned_hours, 0) + ' / ' + format_number(@board.total_plannable_hours, 0)
+    .header-planned-postfix 
+      Stunden verplant
+  .header-planned-row.inperiod-sum
+    .header-planned-prefix 
+      Ausgewählter Zeitbereich:
+    .header-planned-amount
+      = format_number(@board.total_planned_hours(true), 0)
+    .header-planned-postfix 
+      Stunden verplant