added generating iso part plus lotsa updated logic

BOOT_STRUCTURE_PARTS/isolinux/isolinux.cfg

@@ -0,0 +1,28 @@
+DEFAULT live
+LABEL live
+  menu label ^Start or install Ubuntu Remix
+  kernel /casper/vmlinuz
+  append  file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --
+LABEL check
+  menu label ^Check CD for defects
+  kernel /casper/vmlinuz
+  append  boot=casper integrity-check initrd=/casper/initrd.lz quiet splash --
+LABEL memtest
+  menu label ^Memory test
+  kernel /install/memtest
+  append -
+LABEL hd
+  menu label ^Boot from first hard disk
+  localboot 0x80
+  append -
+DISPLAY isolinux.txt
+TIMEOUT 1000
+PROMPT 1
+
+#prompt flag_val
+#
+# If flag_val is 0, display the "boot:" prompt
+# only if the Shift or Alt key is pressed,
+# or Caps Lock or Scroll lock is set (this is the default).
+# If  flag_val is 1, always display the "boot:" prompt.
+#  http://linux.die.net/man/1/syslinux   syslinux manpage