[gitignore] add a few more common scripts to .gitignore
Merge pull request #16 from macpaul/master

[merge] from macpaul: upstream usb and aboot tweaks
[osk5912] remove this old platform and target

Thanks for the years of service osk5912, we'll miss ya.
[arch][arm] remove support for pre armv6 cpus
[arch][arm] reimplement CP15 accessor routines in a much cleaner way

-Implement static inline assembly routines to get to the registers from C.
[arch][arm] clean up exception handling glue a bit
[lib][heap] make the heap 64bit safe, only put magic value if needed
[endian] clean up endian.h

use builtin defines from gcc to set the endian, instead of
calling each arch out separately.
[arch] move arch/ops.h to arch/arch_ops.h and clean up header
[linker scripts] align all the special sections on 8 bytes

This satisfies 64bit architectures.
[include] make the REG* macros cast through uintptr_t

This makes 64bit arches happy if the passed in address
constant is 32bits.
[make] also generate lk.elf.sym.sorted
[arch][arm64] initial port to armv8-a (aarch64)
[platform] add support for Foundation v8 emulator from ARM
[lib][heap] fix fatal crash with DEBUG_HEAP on

DEBUG_HEAP would wipe out the allocated block immediately,
which would crash heap_delayed_free(). Add boolean to allow this
behavior to be skipped during delayed free. Also causes initial
bootstrap of heap to go faster by not completely filling it.
[scripts][qemuarm] make sure the emulated machine has 256MB of ram
[lib][heap] add routine to add new free block to an existing heap
[platform][foundation] add 2nd block of memory (6GB) to the heap
[lib][dlmalloc] clean checkin of dlmalloc
[lib][dlmalloc] get it more or less properly integrated with lk