dhcp: log the configured DHCP client

Also move enumerating the installed DHCP plugins to the beginning
of nm_dhcp_manager_init().

Signed-off-by: Thomas Haller <thaller@redhat.com>
all: consistently include config.h

config.h should be included from every .c file, and it should be
included before any other include. Fix that.

(As a side effect of how I did this, this also changes us to
consistently use "config.h" rather than <config.h>. To the extent that
it matters [which is not much], quotes are more correct anyway, since
we're talking about a file in our own build tree, not a system
include.)
libnm*: fix library gettext usage

Libraries need to include <gi18n-lib.h>, not <gi18n.h>, so that _()
will get defined to "dgettext (GETTEXT_DOMAIN, string)" rather than
"gettext (string)" (which will use the program's default domain, which
works fine for programs in the NetworkManager tree, but not for
external users). Likewise, we need to call bindtextdomain() so that
gettext can find the translations if the library is installed in a
different prefix from the program using it (and
bind_textdomain_codeset(), so it will know the translations are in
UTF-8 even if the locale isn't).

(The fact that no one noticed this was broken before is because the
libraries didn't really start returning useful translated strings much
until 0.9.10, and none of the out-of-tree clients have been updated to
actually show those strings to users yet.)
libnm*: fix library gettext usage (bgo 740071)
dhcp: Fix the DHCP client lookup by gtype
Revert "cli: Finish waiting for device activation when they disconnect"

In case there's already a connection on the device, it traverses to
DISCONNECTED. We shouldn't cease waiting then.

This reverts commit 94a57d5e07b9e3d7f52b4ea3c8b86da9eed28baa.