[beagleboard] Ubuntu kernel and sd card install

Well, "./tools/install_image.sh" is NOT written/designed to do what
you think it can do..

It ONLY installs the kernel image, modules, and firmware to an SD card
with an EXISTING bootloader/Linux OS/etc..

Grab an image from here first:

run the "./setup_sdcard.sh" script..

Then you can run "./tools/install_image.sh" on your new card...