[qmf] Fix double emiting of messageUpdate/messageAdded signal.

Double emition was introduced by this commit:
https://qt.gitorious.org/qt-labs/messagingframework/commit/9aca2eb83a164d3da4bce635eca58e9f3751ca95
When data or properties are updated in the store instance respective messageUpdate/messageAdded
are already emitted.
[qmf] Add test cases for QMailStore::messagePropertyUpdated and QMailStore::messageStatusUpdated signals.

Fix test cases for systems not using accounts framework.
Merge pull request #43 from nemomobile-packages/ipcNotifications

[qmf] Fix double emiting of messageUpdate/messageAdded signal.