Quick fix for Boolean SiteSettings

Boolean SiteSettings are saved as 't' or 'f' on create!, but are being saved as 1 or 0 after update. This quick fix maintains consistency, allowing boolean values to be updated and saved. 

Author: nverba

lib/site_setting_extension.rb

@@ -144,7 +144,7 @@ def add_override!(name,val)
     type = get_data_type(defaults[name])
 
     if type == Types::Bool && val != true && val != false
-      val = (val == "t" || val == "true")
+      val = (val == "t" || val == "true") ? 't' : 'f'
     end
 
     if type == Types::Fixnum && !(Fixnum === val)