func (self *LazyCacheController) invalidateFrontPage() {
	key := util.GetFilenameForIndex(self.webroot_dir)
	self.c.DeleteCache(key)

	key = util.GetFilenameForBoards(self.webroot_dir)
	self.c.DeleteCache(key)
}
// regenerate the front page
func (self *LazyCacheController) RegenFrontPage() {
	key := util.GetFilenameForIndex(self.webroot_dir)
	self.c.Cache(key, self.regen.GenerateFrontPage())

	key = util.GetFilenameForBoards(self.webroot_dir)
	self.c.Cache(key, self.regen.GenerateBoards())
}