Make three changes to code relating to password policy and storage schemes:

- Update the password policy state code to provide a mechanism for obtaining
  clear-text passwords from the user's entry (provided that user has any
  passwords encoded with a reversible scheme).

- Update the password storage scheme API so that it is possible to get the
  clear-text version of a password encoded using the authPassword syntax
  (provided that the scheme is reversible)

- Update the existing password storage scheme implementations to use the
  "{@inheritDoc}" javadoc tag and "@Override" annotation where appropriate.

OpenDS Issue Number:  697