This will allow dynamic configuration depending on property file settings.

Removed connector client bean from XML based configuration and added bean
creation into JavaBased config class. Bean will be created if there is
a property "connector.enable" with value "true" otherwise no bean will
be created wich has the same behavior removing bean definition from XML
configuration file.

No need to change application config - can be done in property file :-)

Added support for an activation webpage and renamed dialog config param
for consistency.

With this configuration both
 - spring security setup
 - bean properties
will be set to values defined in /etc/arsnova/arsnova.properties.

Admins ARE REQUIERED to create production settings file by given example
in /etc/arsnova.

This MUST be done because local developer settings ARE different to
the given example settings.

Deployed settings MUST be prepared by build process to match production
environment.

DO NOT expect local example settings will match all production settings.

This reverts commit 04bd8274.