Remove obsolete stdlib.h from sys/ subtree

Was introduced to allow compilation of NetBSD boot monitor;
is now obsolete since the nominal <stdint.h> is aligned.

While here, fix a bug with weak_alias of putenv(): the MINIX way
is to alias all the "normal" names with the "real" name __foo50,
while it is different from NetBSD's perspective.

Also protect some __RENAME in stdlib.h from _STANDALONE code
(the obsolete copy hided those previously.)
BUGFIX: file perms' for Makefile.gnuhost
BUGFIX: calm down GCC
BUGFIX: utimens(2) declarations...
sys/lib/libz: align with NetBSD
GNU+gitignore: allow speed up to occur!
Drop obsolete <minix/crtso.h>
ramdisk Makefile: CLEANFILES fix
New update_bootcfg, V2; no DESTDIR support any more
Do not rebuild the ramdisk over and over
Force MINIX services to be linked static

This way passing LDSTATIC="" allows to compile the rest dynamically!
binutils: reduce MINIX patch
memory: even more reduced Makefile