Update Vcs fields

Use the canonical URLs. Rename Vcs-Bzr to Vcs-Git and use the more
efficient git protocol instead of http. Point Vcs-Browser to the
gitweb interface.

debian/control

@@ -12,8 +12,8 @@ Build-Depends: dpkg-dev (>= 1.15.8), debhelper (>= 8.1.3~), libdb-dev,
  po4a (>= 0.34-2), autotools-dev, autoconf, automake
 Build-Depends-Indep: doxygen, debiandoc-sgml
 Build-Conflicts: autoconf2.13, automake1.4
-Vcs-Bzr: http://git.debian.org/apt/apt.git
-Vcs-Browser: http://git.debian.org/apt/apt.git
+Vcs-Git: git://anonscm.debian.org/apt/apt.git
+Vcs-Browser: http://anonscm.debian.org/gitweb/?p=apt/apt.git
 
 Package: apt
 Architecture: any