Win32: unify environment function names
Win32: unify environment function names

Environment helper functions use random naming ('env' prefix or suffix or
both, with or without '_'). Change to POSIX naming scheme ('env' suffix,
no '_').

Env_setenv has more in common with putenv than setenv. Change to do_putenv.

Signed-off-by: Karsten Blees <955b63282c975ba379c4995cac1c2e1e7dfebe62@dcon.de>
Signed-off-by: Stepan Kasal <257b363030caa50dbc1cdef9b268d9d56bf639f1@ucw.cz>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git