Initial commit of the bruteforcesettings app

This adds the bruteforce settings app that allows to configure (for now)
subnets that are to be ignored when doing brute force analysis. This can
for example be the LAN since we trust people from there.

* Add app
* Add php tests
* Add js tests

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>