The localization headers are now included via "nm-default.h".
Also fixes several places, where we wrongly included <glib/gi18n-lib.h>
instead of <glib/gi18n.h>. For example under "clients/" directory.
Pop-up menus were slightly mis-aligned in the main window, and even
more mis-aligned in slave-editing windows. Fix that.
Also add a bit of padding to the pop-up window, because it just looks
better that way.
Create a new clients/ subdirectory at the top level, and move cli/ and
tui/ into it, as well as nm-online.c (which was previously in test/,
which made no sense).
cli/ was split into two subdirectories, src/ and completion/. While
this does simplify things (given that the completion file and the
binary both need to be named "nmcli"), it bloats the source tree, and
we can work around it by just renaming the completion file at install
time. Then we can combine the two directories into one and just have
it all under clients/cli/.
