BibEdit: Autocompletion of fields from KBs

*  In a conf variable we declare for which fields
   data will be loaded from which Knowledge Base,
   in order to help user by autocompleting the value.
   Also we choose if the data will be loaded when page is
   loaded or when typing and how will be displayed.

*  addHandler_autocompleteAffiliations is replaced
   from a generic function that handles the behavior for
   any given tag.

*  Handles both static and dynamic KBs

*  Term search is on server-side