Qt: Make Protocol class public API
* lang/qt/src/Makefile.am (qgpgme_headers): Add protocol.h (private_qgpgme_headers): Add protocol_p.h * lang/qt/src/protocol.h: New. From QGpgMEBackend. * lang/qt/src/protocol_p.h: New. From QGpgMEBackend. * lang/qt/src/qgpgmebackend.h, lang/qt/src/qgpgmebackend.cpp (Protocol): Removed.
The backend class does not make much sense anymore as we
only have the GpgME backend obviously. It's purpose was
for Libkleo's Backend abstraction.