Wrapper class for ContactItem

Version 1

    Provides HmacSHA256 authentication wrapper for org.jivesoftware.spark.ui.ContactItem

     

    uses base class values if((authenticationKey == null)||(authenticationKey.length < 64))

     

    no throw constructor, sane fallback values, first draft: critical review requested.

     

    ( newbies excepted from critical review specification under Section 8 )