2.5 beta 12 - add options to backend...

New options in backend settings #107 #20 #81 #95 #93 #63 #96
- global $NMSETTING array to store options (no more new vars)
- removed $NMARCHIVESBY (now in backend / $NMSETTING) #56
- a bit of jQuery to hide/show image options
- new language strings (only in English for now)