Oups, fixed a few mistakes in io.ini: PNG should not be enabled by default...

Oups, fixed a few mistakes in io.ini: PNG should not be enabled by default (since this is an optional plugin) and one PNG key was spelled wrongly...

doc/examples/io.ini

@@ -84,15 +84,15 @@ STATION7	= TUJ3.smet
 COORDSYS	= CH1903
 TIME_ZONE 	= 1
 
-; GRID2D		= ARC
-; GRID2DPATH	= ./
-
-GRID2D		= PNG
+GRID2D		= ARC
 GRID2DPATH	= ./
-PNG_MIN_SIZE	= 800x600
-PNG_WORLD_FILE	= true
-PNG_AUTOSCALE	= false
-PNG_SCALE	= nearest
+
+; GRID2D		= PNG
+; GRID2DPATH	= ./
+; PNG_MIN_SIZE	= 800x600
+; PNG_WORLD_FILE	= true
+; PNG_AUTOSCALE	= false
+; PNG_SCALING	= nearest
 
 METEO		= SMET
 METEOPATH	= ./