Added umax_pp backend (patch from St�phane Voltz

<svoltz@wanadoo.fr>).

backend/umax_pp.conf

@@ -0,0 +1,43 @@
+# For documentation see sane-umax_pp(5)
+
+# GLOBAL #
+
+# size (in bytes) of scan buffer (default: 2 megabyte)
+option buffer 2097152
+
+
+# DEVICES #
+
+# specify the port your scanner is connected to. Possible are 0x378 (lp1)
+# 0x278 (lp2) and 0x3c8 (lp0)
+port 0x378
+
+# the following options are local to this scanner
+# gain for red channel, if not given, will be automatically computed
+# must be between 0 and 15
+option red-gain 8
+# gain for red channel, if not given, will be automatically computed
+# must be between 0 and 15
+option green-gain 4
+# gain for red channel, if not given, will be automatically computed
+# must be between 0 and 15
+option blue-gain 8
+
+# highlight for red channel, if not given, will default to 0
+# must be between 0 and 15
+option red-highlight 2
+# highlight for red channel, if not given, will default to 0
+# must be between 0 and 15
+option green-highlight 1
+# highlight for red channel, if not given, will default to 0
+# must be between 0 and 15
+option blue-highlight 1
+
+
+#
+#
+# model number
+#
+# valid values are 610, 1220, 1600 and 2000
+#
+option astra 1220