Merge branch 'master' of git+ssh://repos-sflphone-git@git.sflphone.org/var/repos/sflphone/git/sflphone

Just needed to pass NULL as an argument for volume when opening streams

Merge branch 'master' of git+ssh://repos-sflphone-git@git.sflphone.org/var/repos/sflphone/git/sflphone

If present, teh call is interpreted as an IP2IP call and not
associated to its account when redialing from call history.

Implemented test suite to place simultanesously 3 calls, then hangup.
Implemented test suite to receive simultaneously 3 calls, then wait for peer hangup.

Merge branch 'master' of git+ssh://repos-sflphone-git@git.sflphone.org/var/repos/sflphone/git/sflphone

Merge branch 'master' of git+ssh://repos-sflphone-git@git.sflphone.org/var/repos/sflphone/git/sflphone