'easy' elf loader for parallella

I prettied up some of the stuff I did a few months ago on the parallella code loader and uploaded it to the home page.

It is still very much work in progress (just a bunch of experiments) but it is currently able to take several distinct epiphany-core programs and relocate and cross-link them to any on-core topology - at runtime. Remote addresses in other cores can be partially resolved automatically (to the local core address offset - suitable for e_get_global_address()) by using weak symbols and the host can resolve symbols by name. By default sections go on-core but .section directives can redirect individual records to specific banks or to global memory. bss/text/data are all supported for any such section using standard names (no 'code' sections!).

Linker scripts are not needed for any of this and the only 'special sauce' is that the epiphany binaries be linked with -r. I mention this because this was the primary driving factor for me to write any of this. I would probably like to replace crt0 as well but that is something for the future (basically remove the bss init stuff).

When I next poke at it I want to work toward wrapping it in an accessible Java API. There is a bit to be done before that though (I think - it's been a while since I looked at it).