As mentioned in [1], the hwmodes "11ng" and "11na" are no longer valid
in BB and become "11g" and "11a". Enabling 802.11n modes are set via the
htmode option now.

Moreover, as the version of BB we rely on with Gluon v2014.4 comes with
a faulty setup script for mac80211 that prevents setting of htmode in
adhoc mode, we replace the default script with a newer one from [2].
Additionally, the mcast_rate value did not get applied correctly in the
BB base of v2014.4, which gets fixed by this exchange as well.

[1] https://dev.openwrt.org/ticket/17541
[2]
https://dev.openwrt.org/browser/trunk/package/kernel/mac80211/files/lib/netifd/wireless/mac80211.sh?rev=43853

The package by now was rather aimed to target on the migration of
TP-Link TL-WR1043NDv2 devices from a pseudo-stable firmware to the
officially stable version 0.6.0.

However, as it might become necessary to change other configuration
values from AA to be compliant with their corresponding values in BB
independent from the particular hardware-type, the package got renamed
to reflect this use. Moreover, as there only is the need to migrate
TP-Link TL-WR1043NDv2 devices once, with the new name the package can be
reused for the migration to Chaos Calmer by adapting the included
scripts.