bugfix
	modified:   application/models/DbTable/Pufferspeicher.php
	deleted:    public/_files/images/waermetauscher/geloetet/BHD21.jpg
	renamed:    public/_files/images/waermetauscher/geloetet/bhd21.png -> public/_files/images/waermetauscher/geloetet/BHD21.png
	new file:   public/_files/images/waermetauscher/geloetet/BHM130.png
	new file:   public/_files/images/waermetauscher/geloetet/BHM24.png
	new file:   public/_files/images/waermetauscher/geloetet/BHM56 CFL.png