Routine Name:	strcat

Description:	Returns new string as concatenation of two strings.

Usage:		new-string = {strcat s1 s2}

Example:	genesis >  echo { strcat "bad" "dog" }
		baddog

Notes:		Unlike the C function of the same name, this routine does not
		modify the string s1.

		You can also concatenate strings using the ``@'' operator.
