ipfw ruleset not loaded after start/restart of captive portal (https://github.com/opnsense/core/issues/49)

this is not a complete fix of the issue, but forces a reload of the ruleset. The behaviour of stopping a zone is not correct now, becasue the ruleset remains active the clients cannot access the internet. A workaround is disabling the zone and stopping it then.

For now the API implementation is pretty basic and mainly targeted at ajax usage, proper authentication for machine to machine use should be implemenented later.

The example /ui/sample/ contains a simple echo service.

add Interfaces to menu system, in the current setup this is the only dynamic item. May need an easier hook in the future, but or now this works fine

changed post handling for apply button.

Awful fix, but works for now.  The package system will be
removed anyway...

While there, clean up the copyright headers into a consistent and
readable style.  Claims that we `strip' copyrights are funny.  :)

- extend menusystem ( documentation on our wiki )

* initial implementation for base\menusystem.
* copied in some of the template parts from the legacy system after cleanup html code.

This is not the fix I have been meaning to push, but openssl_encrypt()
and openssl_decrypt() are too low level.  They do AES-256-CBC, but not
key derivation as well as salt and IV handling.  Getting this 100%
compatible with OpenSSL was the blocker then.  Also, experts have said
that the cipher should not be used anymore, adding more annoyances as
this config output does not have a version information prefix...