simple-uci will now delete an option when nil is passed.

simple-uci will now delete an option when nil is passed.

uci:set_list() will delete the list when nil is passed, so there is no need
to differentiate between the cases.

The generic upgrade script is moved to run after the more specific scripts.
In addition, the script will now remove the configuration sections of
uninstalled VPN packages, so both positive and negative changes of the
default enable state can be migrated correctly.

Based-on-patch-by: Cyrus Fox <cyrus@lambdacore.de>
Fixes: #1187

When a Gluon node is used to connect to an uplink router/DHCP server (for
example in deployments without VPN tunnels), the gw_mode must be set to
server; this should be preserved on upgrades.

Fixes #1196

[Matthias Schiffer: move to proto_gluon_bat0_setup() and default to BATMAN_IV]

gluon-mesh-babel is not merged yet, and once it is, this would lead to a
circular dependency.

To reduce the number of packages that need to be listed in
GLUON_SITE_PACKAGES, this adds a new variable GLUON_FEATURES. Sets of
packages are enabled automatically based on the combination of listed
feature flags.

Site-specified package feeds can provide their own feature flag
definitions.

These packages don't work or don't make sense without batman-adv.

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.

Based-on-patch-by: Christof Schulze <christof.schulze@gmx.net>

While we use the hexadecimal representation as a hash input for simplicity,
it should not be interpreted as case-sensitive.

The new proto will simplify the switch to VXLAN encapsulation.

The next-node MAC address doesn't need to be unique in different
communities, so we can as well add a default value.

Fixes #1130

Reverts d5829d87 ("gluon-mesh-batman-adv-core: disable bridge port
learning on bat0").

Fixes #1121

LEDE recently disabled multicast snooping by default:

https://git.lede-project.org/?p=project/netifd.git;a=commitdiff;h=52541140f8138e31958cdc3d7e42a4029fa6bbc9



Reenable it for Gluon as there have been no confirmed issues for
LEDE and no negative reports concerning Gluon v2016.2.x so far.

Closes #1025.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>

LEDE recently disabled multicast snooping by default:

https://git.lede-project.org/?p=project/netifd.git;a=commitdiff;h=52541140f8138e31958cdc3d7e42a4029fa6bbc9



Reenable it for Gluon as there have been no confirmed issues for
LEDE and no negative reports concerning Gluon v2016.2.x so far.

Closes #1025.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>

We now create bat0 and primary0 independently of the lower mesh interfaces,
making the whole setup a lot more robust. In particular:

- we can't accidentially destroy primary0 because of concurrent setup and
  teardown runs of different interfaces
- bat0 will always exist, even when no mesh interfaces are up (e.g. no link
  on wired mesh)
- interfaces going down and up again will never tear down the whole of
  batman-adv
- we can enable and disable bat0 independently of the lower interface
  states

For simplicity, we don't use different MTUs for compat 14 and 15 anymore,
there's no harm in using 1532 for batman-adv-legacy as well.

In addition, transitive and fixed_mtu now default to 0 instead of an empty string.