E.g. if our locale is pt, which doesn't have localized search plugins,
we'll use one of pt-PT and pt-BR.

Merge branch 'bugfix/8122-better-browser-localization' into bugfix/8036-workaround-for-localized-searchplugins

Conflicts:
	config/chroot_local-includes/usr/local/bin/tor-browser

That is for the various browsers and Tor Launcher. This will make it
possible to drop the browser localization code from Tails Greeter's
PostLogin script, where that really doesn't belong.

Also, this new code is an improvement in that it will pick a "similar"
locale if the specific one we look for isn't available. E.g. with
pt-BR we will get pt, and the Firefox is smart enough to use the pt-PT
langpack.

This reverts commit 7b866f52.

With the upgrade to stable TBB 4.0, all desired locales are available
again.

Conflicts:
	wiki/src/doc/anonymous_internet/i2p.mdwn

We shouldn't let the user believe that they can "configure" Firefox to be the
Tor Browser.

This reverts commit 90e0d322.

Conflicts:
	po/fr.po

Merge remote-tracking branch 'origin/bugfix/8057-translatable-tor-browser-desktop-file' into testing

Merge remote-tracking branch 'origin/bugfix/8035-remove-branding-extension-in-unsafe-browser' into testing

... otherwise, there are great chances to mistakenly and partially upgrade to
Debian testing, and get a non-working system as a result.

This was used to block the upgrade of our equivs-generated iceweasel
package to the one in our APT repos before the TBB migration was
merged into devel. After that, the packages was removed, so this is
not needed any more.

It was added by mistake when adapting the script for the
TBB-migration.

We didn't do this prior to the TBB 4.x bump; 4.x's new directory
layout caused this, so now these must be explicitly deleted.

This instance was forgotten before.

It was a relic of the TBB 3.x times when the profile was located in
the parent directory of the TBB browser files.

Also patch Tails Greeter with the updated path. That patch should
be dropped once it's been upstreamed into Tails Greeter.

The new place corresponds better to where Debian puts the Iceweasel
extensions. Also, it will allow us to drop the useless "Browser"
sub-dir in TBB_INSTALL without having potential collisions (e.g. if
there was a "Browser/extensions").