Fix issue Felix-716

Provides XML-Schemas for core features (core handler, component, handler, instance), compositions, external handlers.
Modifies the manipulator in order to check schema when specified in the XML descriptor.
Tests suites now use schemas.

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@693468 13f79535-47bb-0310-9956-ffa450edef68
29 files changed