Turns out the reason GCC wasn't as smart about startup code for
shared objects as we hoped is because nobody told it to be :D
Change the STARTFILE_SPEC and ENDFILE_SPEC in gcc/config/serenity.h to
skip crt0.o and to link the S variants of crtbegin
and crtend for shared objects.
Because we're using the crtbegin and crtend from libgcc, also tell
libgcc in libgcc/config.host to compile crtbeginS and crtendS from
crtstuff.c.
Toolchain build makes git repo out of toolchain to allow patching
Fix Makefiles to use new libstdc++
Parameterize BuildIt with default TARGET of i686 but arm is experimental