This command will associate a password hash, hostname and
port with a username, storing the info in a password file on the
local filesystem. Subsequent invocations of 4ss command-line scripts
can then automatically look up access info for connecting to a
repository. The location of the password file is determined by the
FTSS_PASSWORD_FILE environment variable. If not set, then the location
is assumed to be a file named '4ss_pass' in the directory determined by the
environment variable HOME (on Unix) or HOMEPATH (on Windows), or the
environment variable WINDIR (on Windows) (one must be set). If the
password file does not exist, it will be created when the first entry
is stored. The location must be writable by the user invoking the
command. At this time, this command does NOT verify that the username,
password hash, hostname and port combination is valid; no repository
connection is made.