More changes to help reflect usage on Rev 2 / 512MB Raspberry Pi's.

Also Makefile tweaks to help improve things somewhat - decided to
read the Makefile manual after some 15 years to updated my make
grey cells somewhat.

New command in the gpio command - readall

build

@@ -10,15 +10,31 @@ if [ x$1 = "xclean" ]; then
   cd ../examples
   make clean
   cd ..
+elif [ x$1 = "xuninstall" ]; then
+  echo Uninstalling
+  echo
+  echo "WiringPi library"
+  cd wiringPi
+  sudo make uninstall
+  echo
+  echo "GPIO Utility"
+  cd ../gpio
+  sudo make uninstall
+  cd ..
 else
   echo wiringPi Build script - please wait...
   echo
+  echo "WiringPi library"
   cd wiringPi
   make 
   sudo make install
+  echo
+  echo "GPIO Utility"
   cd ../gpio
   make
   sudo make install
+  echo
+  echo "Examples"
   cd ../examples
   make
   cd ..