made it so that the encryption value is not removed upon deletion and in...

...stead is set to none so that when network restarts commotiond will not fill in the value.

See issue # 142 https://github.com/opentechinstitute/luci-commotion/issues/142

To test remove encryption using the security menu and then restart networking. If this is successful encryption will still be disabled for the interface. If unsuccessful then encryption will be on for the interface and the password will be set to the commotion default.

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