In addition to significant internal differences in check_site_lib.lua (in
particular unifying error handling to a single place for the upcoming
multi-domain support), this changes the way fields are addressed in site
check scripts: rather than providing a string like 'next_node.ip6', the
path is passed as an array {'next_node', 'ip6'}.

Other changes in site check scripts:
* need_array and need_table now pass the full path to the sub fields to the
subcheck instead of the key and value
* Any check referring to a field inside a table implies that all higher
levels must be tables if they exist: a check for {'next_node', 'ip6'} adds
an implicit (optional) check for {'next_node'}, which allows to remove many
explicit checks for such tables

[Matthias schiffer: rebase, add a few more restrictions]

Some files have received some additional refactoring.

As PROVIDES can be used to replace real packages now, we don't need the
virtual packages as workaround anymore. This also means that the providing
packages don't need to be added to site.mk explicitly anymore when the
default provider is used.

rpcd is not included in our images anymore since switching to gluon-web, so
we don't need to disable it anymore.

This makes the LAN port the PoE master, so the AirGateway can be used to
supply power to another node connected via mesh-on-LAN.

Fixes #608

Nothing outside the config mode depends on luci-base anymore.

We also make use of the boolean support of simple-uci to make scripts
clearer.

Closes #844

The interfaces were accidentially switched when the CPE210 was separated
from the CPE510 code.

Fixes #121

Based-on-patch-by: Tobias Hachmer <tobias@hachmer.de>

Fixes #764

Also backport some patches improving QCA956x support.

Avoid commiting configs inbetween to decrease number of flash writes.

Fixes #714.

This allows to reach the node in setup mode over the same link-local IPv6
address as br-client uses during normal operation.

OpenWrt doesn't set the regdom unless a WLAN device is started. Explicitly set
the regdom in the setup mode to get the correct list of allowed txpower entries
in the planned LuCI module.

This will require site.mk to explicitly pull in the gluon-setup-mode and
gluon-config-mode-core packages.

Moving the scripts to a common directory not only vastly simplifies the
zzz-gluon-upgrade script, but also allows to define an ordering of such
scripts across packages.

By setting setup_mode.skip to true in site.conf the device will skip
setup mode on first boot.

When an early reboot is triggered because an upgrade script has disabled the
config mode, we need to explicitly call /etc/init.d/done, otherwise the overlay
will not be finalized after a firstboot and we get an endless reboot loop.

Since switching to Barrier Breaker/procd, we'd not notice if we were
upgrading from a version before renaming the config file to gluon-setup-mode
as the upgrade scripts run after the preinit.

Fix this by checking later during setup mode init again and rebooting into the
regular run mode if we detect this case.

To start after haveged after the recent update.