dksh4: Build binutils and gcc
.gitignore: Ignore .devkitSH4
dksh4: Get newlib to build
dksh4: Add some basic rules
dksh4: Build general tools
dksh4: Add dreamcast memory map and linker script
dksh4: Add a crt for dreamcast
separate base tools, Snow Leopard fix & MSVC error filter from build rules
add changes for cross compiling 64bit windows toolchains
simplify cross building
update gcc & gdb versions
dksh4: Update binutils to 2.23.1

In addition to just updating the version we'll use for devkitSH4, we
no longer need to patch binutils because all things our patch did are
now in the officially released binutils.