Refactor phonebook code

Refactor phonebook code

Use immediate mode reporting, which means that the individual CPBR
lines are reported up to the core immediately.  This has a couple
advantages:
  - We do not need to malloc/free a bunch of single variables
    and copy them over.  Helps performance.
  - The lines are not buffered up and given to the plugin in one
    shot, instead processing is performed piecemeal.  This helps
    with keeping memory consumption down to a minimum