merge newlib patches into tree

merge newlib patches into tree

Status:
 - freec (old libc) compiles and boots on qemu for x86_{32,64}
 - newlib compiles on x86_64, but does not boot on qemu
 - newlib does not compile on x86_32 due to integer type issues

Changes for the merge:
 - resolved conflicts
 - Patches set -std=gnu99. Changed that to -U__STRICT_ANSI__, which seems
   adequate to keep newlib happy. Keeping -std=c99 might make it easier
   to use other compilers
 - There were changes in the patches to printf format strings, changing
   things like "%zu" to "%lu". Since this does not work for 32-bit archs,
   I 've reverted these changes and defined _WANT_IO_C99_FORMATS for
   newlib, which fixes the original problem.

--HG--
rename : include/string.h => include/freec/string.h
rename : lib/c/src/malloc.c => lib/freec/src/malloc.c
rename : lib/c/src/memcpy.c => lib/freec/src/memcpy.c
rename : lib/c/src/vsnprintf.c => lib/freec/src/vsnprintf.c
rename : lib/c/src/xprintf.c => lib/freec/src/xprintf.c