$ find * -type f |xargs perl contrib/scripts/spdx.pl
  $ git rm contrib/scripts/spdx.pl

We no longer add these. If you use Emacs, configure it yourself.

Also, due to our "smart-tab" usage the editor anyway does a subpar
job handling our tabs. However, on the upside every user can choose
whatever tab-width he/she prefers. If "smart-tabs" are used properly
(like we do), every tab-width will work.

No manual changes, just ran commands:

    F=($(git grep -l -e '-\*-'))
    sed '1 { /\/\* *-\*-  *[mM]ode.*\*\/$/d }'     -i "${F[@]}"
    sed '1,4 { /^\(#\|--\|dnl\) *-\*- [mM]ode/d }' -i "${F[@]}"

Check remaining lines with:

    git grep -e '-\*-'

The ultimate purpose of this is to cleanup our files and eventually use
SPDX license identifiers. For that, first get rid of the boilerplate lines.

From the files under "shared/nm-utils" we build an internal library
that provides glib-based helper utilities.

Move the files of that basic library to a new subdirectory
"shared/nm-glib-aux" and rename the helper library "libnm-core-base.la"
to "libnm-glib-aux.la".

Reasons:

 - the name "utils" is overused in our code-base. Everything's an
   "utils". Give this thing a more distinct name.

 - there were additional files under "shared/nm-utils", which are not
   part of this internal library "libnm-utils-base.la". All the files
   that are part of this library should be together in the same
   directory, but files that are not, should not be there.

 - the new name should better convey what this library is and what is isn't:
   it's a set of utilities and helper functions that extend glib with
   funcitonality that we commonly need.

There are still some files left under "shared/nm-utils". They have less
a unifying propose to be in their own directory, so I leave them there
for now. But at least they are separate from "shared/nm-glib-aux",
which has a very clear purpose.

(cherry picked from commit 80db06f768e47541eae7d66ef48fbe47bf1a69ce)

In the past, the headers "linux/if.h" and "net/if.h" were incompatible.
That means, we can either include one or the other, but not both.
This is fixed in the meantime, however the issue still exists when
building against older kernel/glibc.

That means, including one of these headers from a header file
is problematic. In particular if it's a header like "nm-platform.h",
which itself is dragged in by many other headers.

Avoid that by not including these headers from "platform.h", but instead
from the source files where needed (or possibly from less popular header
files).

Currently there is no problem. However, this allows an unknowing user to
include <net/if.h> at the same time with "nm-platform.h", which is easy
to get wrong.

By using nm_memdup().

Except in shared/nm-utils/nm-compat.c, which may not include
"shared/nm-utils/nm-shared-utils.h".

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

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

Will be used next...

Routes are complicated.

`ip route add` and `ip route append` behaves differently with respect to
determine whether an existing route is idential or not.

Extend the cmp() and hash() functions to have a compare type, that
covers the different semantics.