Update Vcs-* headers to use salsa repository.
Fixed-Lintian-Issues:
 source: vcs-obsolete-in-debian-infrastructure vcs-svn http://svn.debian.org/wsvn/pkg-voip/asterisk-prompt-fr-proformatique/?op=log
 source: vcs-field-bitrotted http://svn.debian.org/wsvn/pkg-voip/asterisk-prompt-fr-proformatique/?op=log https://anonscm.debian.org/viewvc/pkg-voip/asterisk-prompt-fr-proformatique
