Externalize all WAR configuration

The main webapps (core and console) require several configuration files (.properties) to work properly.
Currently such configuration files need to reside into webapps' classpath.

Ideally it should be possible to define a configuration directory, defined via a Maven property, where all such files can be loaded from: this would allow to implement some handful deployment scenarios (e.g. deploy the same .war files either in test and production environments).

The same idea is to apply to e-mail templates.