On boot, unblock bluetooth, wifi, wwan and wimax; block every other type of wireless device.

The ticket says to leave Bluetooth alone, but if we do that and it's disabled by
default by the firmware or whatever, then it would have no chance to get
connected devices, and then the design we decided for
todo/protect_against_external_bus_memory_forensics could not be implemented for
this protocol. So, we unblock it.
Merge branch 'devel' into feature/set-wireless-devices-state
Add design doc for wireless devices handling.
Add an anchor.
Add end-user documentation to unblock a wireless device.
Merge branch 'devel' into feature/set-wireless-devices-state
Merge branch 'devel' into feature/set-wireless-devices-state
Use 'enable' instead of 'block'
Do not use bullet markup for steps

That was used in older documentation but takes a lot of visual and
mental space for nothing.
Fix identation
Shorten
Be more explicit
Rephrase
Avoid using the past
Typo
Use a more precise page name
Update whisperback help according to recent doc changes
Add a summary of how to write useful bug report
GnuPG: don't connect to the preferred keyserver specified by the key owner.

This feature opens the door to a variety of subtle attacks.
GnuPG: locate keys only from local keyrings.

This is probably the default, but better safe than sorry.