[PLINK-258] - Fixing salt issues. Supporting additional configuration options to the PasswordCredentialHander.
Adding volatile keyword to the lastRenewTime field. DefaultSecureRandomProvider now uses Random.nextLong as a seed when no key length is provided.
Merge branch 'PLINK-258'
Merge pull request #185 from pedroigor/master

[PLINK-258] - Fixes for salt generation and more configuration options to the PasswordCredentialHandler.