Added a metadata validation tool.

Updated documentations and included a metadata validation tool.


The IdP proxy comes with a web application tool that will generate the
EntityAttributes structure for a set of given service providers and social services.
The tool also includes a metadata verification that can be used to verify that
the EntityAttribute is included correctly in the metadata.

For metadata generation:   http://myProxyIdpIP:port/metadata
For metadata verification: http://myProxyIdpIP:port/metadata/verify