Update to SOL003 2.4.1 and some bugfixes

Udating the definitions to the 2.4.1 version of SOL003.

  - All interfaces are ready for review
  - WWW-Authenticate was removed from responses except the 401-s and in places where
    it is explicitly mentioned in the description
  - vnfInstanceIds and vnfInstanceNames added to VnfInstanceSubscriptionFilter
  - Inline types of VnfInstance are move to the main definition
  - Description of GET of Individual VNF instance fixed

Change-Id: I06e16a69cc5338e39aef8d41699dea33171ed1d2
Signed-off-by: Gergely Csatari <gergely.csatari@nokia.com>