Initial commit
Added various docs
Added readme
Synced to updated rust-core
Extracted ld section layout to dedicated file
More fixes to dependency tracking code that still sucks
Use MBED board only for lpc_17xx mcu
stm32f4 code is now functional, more improvements

 * stm32f4 code is functional, added default board config for
   stm32f4discovery, app_empty and app_blink are working;
 * refactored Timer code, wait() is now implemented in the trait;
 * updated gdbinit with helper functions for stm32f4 debugging;
 * added basic support for code configuration via Rakefile's features
   and platform-specific features.

Notes on stm32f4:

The only tested configuration is 168MHz, others should possibly work as
well.

All the gpio module code is implemented in pin.rs, as stm32f4 implements
pin mode selection in totally different way.

There's no pin map yet, the thing is huge.

Timer support is *very* basic, only Timer2 for now just to make
app_blink work. Why this thing has so many timers? Sometimes I feel like
working with cortex-a.

LLVM's new __morestack is broken on stm32f4 as well.
Removed old demo code
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Merge pull request #5 from waffle-iron/master

added waffle.io Badge
Systick support; new weak ISRs; new Rakefile; cleanups; debug interface.

 * systick is now supported as part of cortex_m3. It expects the 10ms
   register to have reasonable value for 10ms ticks;
 * ISR code extracted to dedicated .s file until rust adds support for
   weak symbols;
 * ISRs should be re-exported in a strange fasion. Currently there's a
   helper macro route_isr! to do that;
 * removed all the deprecated macros from ioreg;
 * new Rakefile syntax should make it a bit more readable;
 * added a pinmap template for stm32f4, now need to figure out what to
   do with it;
 * .ARM.exidx is now removed from elf file, thou shall not unwind;
 * added os::debug that is a globally available "safe" CharIO interface
   backed by UART.
Basic multitasking implementation.

 * added multitasking feature to Rakefile;
 * simpler debugging with gdb 'reload' command;
 * applications are now rlibs. This breaks all the demo apps other than
   app_sched;
 * added a basic not-really-round-robin task scheduler;
 * added app_sched multitasking demo;
 * cleaned up ISR assembly code;
 * systick irq can now be disabled and enabled to allow critical
   sections;
 * added scheduler ISRs for systick, pendsv and svcall;
 * syscall interface is implemented in os::syscall;
 * added hal::stack to provide methods to manipulate stack-related data;
   the definition of __STACK_LIMIT moved to linker script;
 * added lib/app.rs, the final linking object that re-exports required
   symbols from libzinc.
Fixed most of the demo apps. app_systick is still broken.
Multitasking code is now optional.
Move the Cortex-M specific registers into cortex_m3 directory.
Copyright header
Merge pull request #9 from bharrisau/armregs

Move the Cortex-M specific registers into cortex_m3 directory.
Removed deprecated interfaces.
Various cleanups and documentation changes