The history takes in consideration all the outgoing and incoming calls
You can't call back every calls from history tab (those you don't hang up on)

Conflicts:

	sflphone-gtk/src/calltree.c

Saved with the preferences

Conflicts:

	sflphone-gtk/src/Makefile.am
	sflphone-gtk/src/calllist.h
	sflphone-gtk/src/calltree.h
	sflphone-gtk/src/menus.c

Comments every methods in every header

But introduces a bug: sometimes seg fault

Add ERROR_AUTHENTIFICATION and ERROR_NETWORK to the account state

Registration possible if the account is in ERROR state

Adding error state
Global variables on the client side moved in sflphone_const.h