[Feature Request] Allow user to edit BB server landing page or allow for a drop in html file

[ampersandru]

For optional increased security, I think it would be a good idea to let the user set their own message of the BB server landing page or allow users to edit/drop in a html file to replace the default message.

This is especially important for those with static URLs - it would be ideal not to advertise specific services you are running incase of 0-days or exploits that might be discovered.

[zlshames]

done, internally, development branch