adapt svga driver better to 0.5 API; make it take options from config file

LCDd.conf

@@ -520,15 +520,31 @@ Port=0x378
 ## stv5730 driver ##
 [stv5730]
 
-# Port the device is connectoed to [default: 0x378]
+# Port the device is connected to [default: 0x378]
 Port=0x378
 
 
 
 ## SVGAlib driver ##
 [svga]
-# No options.
-# You should of course have your svgalib configured correctly.
+
+# svgalib mode to use [default: G320x240x256; legal: supported svgalib modes]
+#Mode=G640x480x256
+
+# set display size [default: 20x4]
+Size=20x4
+
+# Set the initial contrast [default: 500; legal: 0 - 1000]
+# Can be set but does not change anything internally
+Contrast=500
+
+# Set the initial brightness [default: 1000; legal: 1 - 1000]
+Brightness=1000
+
+# Set the initial off-brightness [default: 500; legal: 1 - 1000]
+# This value is used when the display is normally
+# switched off in case LCDd is inactive
+OffBrightness=500