This commits cleans up 3 segfaults/valgrind errors due to access
to freed memory.

1. The spy wasn't clearing conn_spy causing the svc_destructor to try
   to clear the spy destructor when the spy was already freed

2. get_config_service was not setting the svc_destrcutor on services
   depending on the orderof frees at exit this was causing the spy
   destructor to try to access freed memory because it was not
   neutralized when the service was freed.

3. at exit the mt_ctx could be freed before services causing the
   svc_destrcutor to try to access freed memory when removing the
   service from the service list in the monitor context.

dbus_connection_send_with_reply() will report success and return
a NULL pending_reply when the connection is not open for
communication. This patch creates a new wrapper around
dbus_connection_send_with_reply() to properly detect this
condition and report it as an error.

Fixes: #221

Upon receiving SIGHUP, the monitor signals all services to reopen their
debug logs. It is also possible to signal individual services to reopen
their particular files.

Fixes: #332

Logs from confdb with missing '\n' in the DEBUG statements annoyed me so
I decided to fix them. I also made a quick grep through the code and
found other places so I fixed them too.

We disabled live reconfiguration a long time ago with the intent
of fixing it so that it wasn't completely broken, but we've
decided that live updates are too delicate to handle all cases
gracefully. For the forseeable future, we will rely on process
restart for updating the configuration.

Furthermore, we had not completely disabled live updates. It would
still attempt to run if we sent a SIGHUP. This has also been
eliminated.