Short term:

- use .ini-like layout for entropy config

- conditional deps:
  enabled with ETP_PORTAGE_CONDITIONAL_DEPS_ENABLE
  Test package generation and entropy client behaviour
  (both direct and inverse dependencies calculation)

- rewrite entropy.Security() to be O(1) (dump sulfur first)


 Long term:

 - move variables away from etpConst
   (to SystemSettings || Client || Server as static methods)
 - Python 3.3+ support