References in text to bstrcat should be replaced with bconcat

I'm guessing it's just a name change that hasn't gone through everywhere?

ack bstrcat leaves the following occurances:

bstrlib/bsafe.c
37:     fprintf (stderr, "bsafe error: strcat() is not safe, use bstrcat instead.\n");
64:     fprintf (stderr, "bsafe error: strncat() is not safe, use bstrcat then btrunc\n\torcstr2tbstr, btrunc then bstrcat instead.\n");

bstrlib/bstrlib.txt
187:        bstrcat (p = bfromcstr ("Hello,"), q = bfromcstr (" World"));
191:failure to allocate memory) both bstrcat and bdestroy will recognize it and

It left me hanging when trying out one of the earliest code snippets in bstrlib.txt.

Hugs