A utility class for encoding a string with SHA-1 hash and comparing the equality of an encoded string
Uses a randomly generated salt with a default length of 2-4 (public class members, changeable if needed)
Implementation adapted from the examples provided at:
http://www.koders.com/java/fid9D416D88A1524FCC491B342D7B6A2E70694691D7.aspx
http://www.bombaydigital.com/arenared/2003/10/10/1
http://www.glenmccl.com/tip_010.htm
Detects if there is no Authentication object in the SecurityContext, and populates it
with a remember-me authentication token if a RememberMeServices
implementation so requests.