Function session_salted_md5

Make a salted MD5 string, given a string and (possibly) a salt.

If no salt is supplied we will generate a random one.

Package: awl\Utilities
Copyright: Catalyst IT Ltd, Morphoss Ltd http://www.morphoss.com/
License: GNU LGPL version 3 or later
Author: Andrew McMillan andrew@mcmillan.net.nz
Located at AWLUtilities.php

Parameters summary
`string`	`$instr`	The string to be salted and MD5'd
`string`	`$salt = ""`	Some salt to sprinkle into the string to be MD5'd so we don't get the same PW always hashing to the same value.

Return value summary
`string`	The salt, a * and the MD5 of the salted string, as in SALT*SALTEDHASH