bugfix for the project update case

Author: jkraemer

lib/redmine_gtt/patches/project_patch.rb

@@ -8,7 +8,7 @@ def self.apply
           Project.class_eval do
             safe_attributes "geom"
             has_and_belongs_to_many :gtt_tile_sources
-            after_save :set_default_tile_sources
+            after_create :set_default_tile_sources
           end
         end
       end
@@ -44,6 +44,10 @@ def geom=(g)
         end
       end
 
+      def enabled_module_names=(*_)
+        super
+        set_default_tile_sources
+      end
 
       def set_default_tile_sources
         if gtt_tile_sources.none? and module_enabled?(:gtt)