COVER: Netduino 2 Machine Model

---CHANGELOG---
PUBLIC
This patch series adds the Netduino 2 Machine to QEMU

Information on the board is avalible at:
http://www.netduino.com/netduino2/specs.htm

The git tree can be found at:
https://github.com/alistair23/qemu/tree/netduino2.6

This patch series makes some changes to the armv7m_init function
that allows the code to be reused with the Netduino 2 and the
Stellaris machines.

Some example code that runs on QEMU is avaliable at:
at: https://github.com/alistair23/CSSE3010-QEMU-Examples

There are more devices in the works, I figured I would just start
with these three

V6:
 - Rename the three devices to STM32FXX*
 - Correct the timer to use ns
 - Correct the number of devices that are inited
 - Rename memory regions
V5:
 - Remove the reset changes based on the ELF entry
V4:
 - Rebase
 - Correct timer units
V3:
 - Correct the timer interrupts
 - Update debug printing
 - Remove the sram_size argument from armv7m_init
---END---

Signed-off-by: Alistair Francis <alistair23@gmail.com>