Normalize coding style by removing consecutive empty lines from C
sources and headers.

https://github.com/NetworkManager/NetworkManager/pull/108

Use the same form everywhere: "TRANSLATORS" instead of "Translators".
The manual also seems to prefer the upper-case form [1].

  $ sed 's/\<Translators\>: /TRANSLATORS: /g' $(git grep -l Translators) -i

[1] https://www.gnu.org/software/gettext/manual/gettext.html

https://bugzilla.gnome.org/show_bug.cgi?id=794658

If an operation is cancelled through the GCancellable, then the idiom is
that the operation is always cancelled, even if it has finished
successfully. To ensure this is the case, add calls to
g_simple_async_result_set_check_cancellable everywhere.

Without this, e.g. gnome-control-center will crash when switching away
from the power panel quickly, as the NMClient creation finishes
asynchronously and g-c-c assume that G_IO_ERROR_CANCELLED is returned to
ensure it doesn't access the now invalid user_data parameter.

https://bugzilla.gnome.org/show_bug.cgi?id=794088

It's very likely that the product said something that was filtered out
by the fixup, such as "PCI Ethernet" or "Wi-Fi Adapter". Use a generic
type name in place of it.

The database has a chance to fix up over garbage strings from the device
properties and we're now known to be reasonably good at fixing up crap
there.

The product names are generally of rather poor quality. The product name
is no place to enumerate product capabilities, the bus it's attached on
and similar nonsense.

The hwdb generally contains the strings of rather poor quality,
especially when it comes to sensibly presenting them to the user and
they need various cleanups.

While the following patches add fixups, this one splits out vendor
fixups, because it turns out that a different set of fixups is needed
than for products.