configs/mx1ads:  This commit removes board support for the mx1ads board.  That board support was never completed and I no longer even have the hardware.  The unfinished board support is still available in the Obsoleted repository if anyone would ever like to resurrect it.

    BCM2708:  Add enough infrastructrue (more stubs) to get a clean compilation of the Pi Zero configuration (with many undefined things at link time).

    BCM2708:  Add basic interrupt handling logic

    BCM2708: Add interrupt register definitions.

    BCM2708:  Add irq.h header file

    BCM2708/Pi zero:  bcm_boot.c and bcm_memorymap.h now compile.  Added pizero linker script.

    BCM2708/Pi Zero:  Add Make.defs needed to build.

    arch/arm/include/bcm2708, arch/arm/src/bcm2708, configs/pizero:  Add some basic build and configuration logic.

    configs/pizero:  Add some basic structure of the Rasperry Pi Zero port.

    Created directory configs/pizero.  Nothing there now but a README.txt file.

    Add initial boot.c and memorymap.c files
    Author: Alan Carvalho de Assis <acassis@gmail.com>

    Add AUX/UART/SPI registers definition
    Author: Alan Carvalho de Assis <acassis@gmail.com>

    Pizero GPIO registers
    * Initial commit to add GPIO definitions
    * Add remaining GPIO registers definition
    Alan Carvalho de Assis <acassis@gmail.com>

    BCM2708 memory map:  Add VBASE defintions; fix VCSDRAM address per Alan; move all virtual address to the bottom of the file to avoid confusion -- top is all physical address; bottom is all veritural address.

    Add initial memory map to BCM2708/BCM2835
    Alan Carvalho de Assis <acassis@gmail.com>

Build System:  It is no longer necessary to have a unique Make.defs file for each configuration.  A board may share a common Make.defs file in the scripts directory.

configs:  Add readme for B-L465E-IOT01A Development kit.  This port is currently under consideration (but may not actually happen)

Revert "Add a placeholder for nucleo-64 boards.  Currently these are in various directories nucleo-f303re, nucleo-f334r8, and nucleo-l476rg but need to be consolidated here because these are all the same boards."

This reverts commit 935cc4e3.

Add a placeholder for nucleo-64 boards.  Currently these are in various directories nucleo-f303re, nucleo-f334r8, and nucleo-l476rg but need to be consolidated here because these are all the same boards.

Add configuration to prevent selection of Windows native toolchains when using Ubuntu under Windows 10

Back out most of 34be3e7c and update README again.  Windows native tools cannot be used with Ubuntu under Windows 10 now.  For Cygwin, that support depends on the 'cygpath -w' tool to convert POSIX paths to Windows paths.  There is no corresponding tool for Ubuntu under Windows 10.