warning: new file /sys/src/ape/lib/bsd/sethostent.c not on sources

added sethostent() and a few xxx_r() functions to APE.

I added:
	ctime, localtime, gmtime, asctime, strtok, strerror,
	getlogin, ctermid, tmpnam, 

Solaris 8 also includes these...

	gethostbyname, gethostbyaddr, getservbyname, getservbyport, 
	getprotobyname, getnetbyname, getnetbyaddr, getrpcbyname, 
	getrpcbynumber, getrpcent, rand, readdir, getpwent, 
	getpwnam, getpwuid, getspent, fgetspent, getspnam, getgrnam, 
	getgrgid, getnetgrent, getrpcbyname, tempnam, fgetpwent, 
	fgetgrent, ecvt, gcvt, getservent, gethostent, getgrent, fcvt 

however I don't need them. 

I was going to add readdir_r() but it is "considered harmful"
[http://womble.decadentplace.org.uk/readdir_r-advisory.html]
so it seems chirlish to implement it.

All the reentrant function prototypes are under the control of
_REENTRANT_SOURCE in the hearder files.

-Steve