Updated dbus to 1.10.20.

D-Bus 1.10.20 (2017-06-29)
==

The “suggesting a delivery gone horribly wrong” release.

Fixes:

• Fix a reference leak when blocking on a pending call on a connection
  that has been disconnected (fd.o #101481, Shin-ichi MORITA)

• Don't put timestamps in the Doxygen-generated documentation, for
  closer-to-reproducible builds (fd.o #100692, Simon McVittie)

• Avoid an assertion failure when connecting to a semicolon-separated
  series of addresses, one of which fails (fd.o #101257, Simon McVittie)

Documentation:

• Update git URIs in HACKING document to sync up with cgit.freedesktop.org
  (fd.o #100715, Simon McVittie)

(wiz)