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(cherry picked from commit fefd58f307015c19bfb9ef1d3d350380c4245c6d)
(cherry picked from commit a5740cd5)

# Conflicts:
#	coreapi/private.h

Add message command to linphone-daemon, to send text message. Outgoing message's states are notified through events, and incoming messages are notified with events too.
Refactor the code by adding a new Event class, so that there is no more confusion between responses and events as it was before.

avoid downloading tmp certificate file into source directory to secure // build, specially in case of multi arch.

 Conflicts:
	tester/flexisip_tester.c