OpenSDI2 configuration system


This pull request contains the first implementation (engeneering + an implementations using properties files) of the OpenSDI configuration system, the initial proposal can be found at this [1] link.

All the developments have been done mainly in the opensdi2-core so you can find the related unit test in that module.

As agreed the first module has been migrated to the usage of the new config system is the **filemanager**. 
You can test it using the example datadir versioned in the repository root, run the application setting the **OSDI_CONFIG_DIR** environment variable with the path of the datadir(-DOSDI_CONFIG_DIR=D:\work\configurations\OPENSDI2_CONFIG) then use the links below to call the service:
* http://localhost:9191/opensdi2-manager/mvc/fileManager/extJSbrowser?scopeID=filemanager&instanceID=instance1
* http://localhost:9191/opensdi2-manager/mvc/fileManager/extJSbrowser?scopeID=filemanager&instanceID=instance2

A draft of the documentation can be found at this [2] link, once the pull req will be accepted that document should be published in a better organized way. It also contains link to 2 google docs documents (diagrams).

This is a SQUASHED version of the branch **configuration_system_master_20141112**, below the commit messages:

* more test, fixes, and properties files Implementation
* Finished Implementation of configDAO using properties properties
* fixes to propertiesDAO
* improvements to exceotion handling, configuration interceptor, usage of configuration in filebrowser module
* fixes to log4j in order to log properly into the jetty console
* Refactoring of DataDirHandler + fixed tests
* Converted FileManager to the usage of the new configuration system, added an example datadir
* classes and packages names refactoring


[1] https://github.com/geosolutions-it/OpenSDI-Manager2/wiki/Proposal-%231:-Application-Core-Configuration-and-Conventions
[2] https://github.com/geosolutions-it/OpenSDI-Manager2/wiki/How-to-develop-a-new-OpenSDI2-Manager-module-%5BDRAFT-27-11-2014%5D
In my opinion yes, The application config directory can store also other files that are not strictly related to the module/instances configurations and I think it is good to have a config directory handler decoupled from the configurations DAO.