Before this commit, some *.po files contained the same translation
twice within the same file. While this did not led to errors in
gluon yet, it is still invalid. This commit fixes that and removes
the duplicates.

Add the `wifi5.outdoor_chanlist` site configuration that
allows specifying an outdoor channel range that can be
switched to for regulatory compliance.

Upon enabling the outdoor option the device will
 - configure the `outdoor_chanlist` on all 5 GHz radios
 - which may enable DFS/TPC, based on the regulatory domain
 - disable ibss/mesh on the 5 GHz radio, as DFS *will*
   break mesh connections
 - allow for htmode reconfiguration on 5 GHz radios

The outdoor option can be toggled from
 - Advanced Settings
   - W-LAN
     - Outdoor Installation

The `preserve_channel` flag overrules the outdoor channel
selection.

Fixes #219