Provide a more flexible and less strict default configuration of InternalPasswordCredentialInterceptors

The default password credential validation and handling is rather (military) strict in that it

• enforces a password change on first login
• keeps a history of already used (and thus not allowed to be used again) passwords
• sets a max lifespan on each password
• requires a minimum length of 6 with at least 2 digits.

All these rules and features are already configurable through springframework right now.
But because these are enforced by an interceptor hierarchy, disabling one rule like max lifespan or required password change on first login,
requires replacing an interceptor or modifying the interceptor hierarchy.

I'm going to provide a more flexible solution by changing the DefaultCredentialHandler to accept a list of InternalPasswordCredentialInterceptors in its constructor.
The DefaultCredentialHandler will then invoke each provided interceptor in the list .
And I will breakdown the current complex interceptors into simple interceptors which each only providing/enforcing only one rule or feature:

• password encoder: encodes a not-yet-encoded password on first load
• password history: configurable history of passwords which cannot be reused
• change password on first use (note: the password encoder interceptor will enforce this when the not-yet-encoded password turns out to be invalid)
• password expiration: configurable password max lifespan
• max authentication failures: configurable number of validation errors (in a row) allowed

Once this is in place and working we can decide which of these interceptors should be used in the default configuration for Jetspeed-2.
And I will provide a document how to use these interceptors including an example how to enforce the same strict rules of our current configuration.

Further enhancements I'd like to implement are:

• only temporarily disabling of a credential after max authentication failures (like 30 minutes)
• disable password expiration for certain credentials (for example an admin credential) and/or certain users/groups/roles
  But I'm not sure yet I'll be able to provide these additional features without database model enhancements.