Post-Build USB installation (#65)

There were no hints for the installation on a usb stick, i think it would be good to add something.

README

@@ -43,6 +43,10 @@ Note:
   - it will create ISO and TAR files for you in /tmp
   - make sure you have enough free space in /tmp to handle it
   
+* If you want to use the Live Kit on a USB you have to either
+  - use Windows to execute the bootinst.bat file in the $NAME/boot folder
+  - or use Linux to execute the shellscript bootinst.sh in the $NAME/boot folder.
+
 * You will need the following packages to be installed:
   - squashfs-tools
   - genisoimage or mkisofs