Overload the certificate and key properties to allow paths to the
certificates and keys using a special prefix for the property data.
Add API to libnm-util for easy certificate path handling, and
documentation for NMSetting8021x.
0.7 requires dbus 1.1 or greater (for system bus activation), so make that
explicit, and remove compat code for D-Bus 0.6 and earlier. Consolidate
the various glib pkgconfig checks into one, since most anything will require
gthread, glib, and gobject anyway. Fixup the docs makefile to be more
automake-compatible and let 'make clean' actually work correctly when
docs are built.
This caused the 'autoconnect' property of NMSettingConnection to not
get updated in some cases (as when a system setting plugin noticed a
change to autoconnect=true and emitted the Updated signal, which wouldn't
contain the new value). Add a testcase for setting default values too.
