cli: use g_print/g_printerr rather than printf/fprintf

Use g_print() and g_printerr(), which wrap printf() and
fprintf(stderr,...), but handle conversion from UTF-8 if the locale is
using a different character set.
libnm-core: add nm_utils_wifi_strength_bars(), use it in nmcli and nmtui

Add nm_utils_wifi_strength_bars(), which figures out whether the
terminal can display graphical wifi strength bars, and converts a
numerical value to the appropriate Unicode or ASCII characters.

This also now takes into consideration the fact that the console font
doesn't contain all of the necessary characters, so we can't display
the graphical bars there. (rh #1131491)
tui, cli: improve printing of Wi-Fi strength bars (rh #1131491)
po: update Tamil (ta) translation (bgo #737419)

https://bugzilla.gnome.org/show_bug.cgi?id=737419
po: update Kannada (kn) translation (bgo #737131)

https://bugzilla.gnome.org/show_bug.cgi?id=737131
po: update Telugu (te) translation (bgo #737204)

https://bugzilla.gnome.org/show_bug.cgi?id=737204
po: update Hindi (hi) translation (bgo #737097)

https://bugzilla.gnome.org/show_bug.cgi?id=737097
po: update Marathi (mr) translation (bgo #737057)

https://bugzilla.gnome.org/show_bug.cgi?id=737057
po: update Assamese (as) translation (bgo #736849)

https://bugzilla.gnome.org/show_bug.cgi?id=736849
po: update Swedish (sv) translation (bgo #737086)

https://bugzilla.gnome.org/show_bug.cgi?id=737086
config: refactor parsing of boolean config values

Allow for the special values "1" and "0". Also, ignore the
letter case when comparing the configuration value.

Signed-off-by: Thomas Haller <thaller@redhat.com>
auth: rename file nm-manager-auth.* to nm-auth-utils.*

Signed-off-by: Thomas Haller <thaller@redhat.com>
build: generate man/NetworkManager.conf.xml by autoconf

Signed-off-by: Thomas Haller <thaller@redhat.com>
auth: rework polkit autorization to use DBUS interface directly

This makes NetworkManager independent of <polkit/polkit.h>
development headers and libpolkit-gobject-1.so library.
Instead communicate directly with polkit using its DBUS
interface.

PolicyKit support is now always compiled in. You can control
polkit authorization with the configuration option
  [main]
  auth-polkit=yes|no

If the configure option is omitted, a build time default
value is used. This default value can be set with the
configure option --enable-polkit.

This commit adds a new class NMAuthManager that reimplements the
relevant DBUS client parts. It takes source code from the polkit
library.

https://bugzilla.gnome.org/show_bug.cgi?id=734146

Signed-off-by: Thomas Haller <thaller@redhat.com>
auth: support disabling POLKIT authentication entirely at compile time

Let the user completly disable polkit authentication by
building NM with configure option  '--enable-polkit=disabled'.

In that case, configuring 'main.auth-polkit=yes' will fail all
authentication requests (except root-requests, which are always granted).

This reduces the size of the NetworkManager binary by some 26KB (16KB
stripped).

Signed-off-by: Thomas Haller <thaller@redhat.com>
auth: merge branch 'th/bgo734146_polkit'

Implement polkit requests by directly using the DBUS interface.
This makes NetworkManager independent from libpolkit-gobject-1 library.

https://bugzilla.gnome.org/show_bug.cgi?id=734146

Signed-off-by: Thomas Haller <thaller@redhat.com>