update the euid and call cygheap->user.set_name. Remove special
handling of ILLEGAL_UID.
(setgid32): Add a debug_printf. On Win95, always set the egid.
Remove special handling of ILLEGAL_GID. Do not compare gid and gr_gid.
* child_info.h (class cygheap_exec_info): Remove uid.
* spawn.cc (spawn_guts): Do not set ciresrv.moreinfo->uid.
* dcrto.cc (dll_crt0_1): Always call uinfo_init.
* uinfo.cc (uinfo_init): Reorganize and close handle if needed.
(cygheap_user::ontherange): Do not call internal_getpwnam if pw is NULL.