Added U-Boot binary and configuration files:
- u-boot.bin - This is the u-boot binary. This is lanunched instead of kernel.img. This was compiled from the source at http://github.com/gonzoula/u-boot-pi
- boot-tftp.cmd - This is the uncompiled u-boot script. This tells u-boot to start the usb and ethernet devices, download kernel.img, and jump to 0x10000
- boot.scr - This is the compiled u-boot script. This must keep its name, u-boot looks for this file specifically.
- uEnv.txt - This contains the environment variables for u-boot. For tftp you must assign an ip-address to the RPi and configure where the tftp server is
- config.txt - This file has been updated to tell the GPU to load u-boot.bin instead of kernel.img
Added U-Boot readme
Added U-Boot License
Corrected GitHub URL for U-Boot
Removed u-boot binaries
Added the source for the RPi port of U-Boot

This is not yet integrated into the Xinu build process,

U-boot can be built by:
1. CROSS_COMPILE=arm-none-eabi-
2. export CROSS_COMPILE
3. make rpi_b
The output file of interest is u-boot.bin

The u-boot script can then be built using mkimage which was also compiled in the previous step.

./tools/mkimage -A arm -O linux -T script -C none -d tftp-boot.cmd boot.scr
Excluded u-boot from the existing build
Merge pull request #8 from zachberger/pi-hw2-uboot

Pi hw2 uboot