Change panel operations

Disease panels from PanelApp and Cancer Gene Census are going to be made available in this URL: http://resources.opencb.org/opencb/opencga/disease-panels/. These panels will be updated with every new OpenCGA release.

The inclusion of this new resource makes some things easier when we want to import panels. This means that:

[x] Old /admin/catalog/panel web service will be removed because we OpenCGA will not allow the concept of global panels as we had it anymore. All global panels will be deleted.
[x] Any reference to global panels will be removed from the Web services (and from the manager implementation)
[x] /panel/create WS will now accept a list of sources to import panels from and an optional list of ids in case the user wants to make a selection among all the available ones.
[x] A new panel host option will be added to the configuration file. By default, it will be pointing to our resources URL, but users will be able to add their own panel resource URL.
[x] A new admin.sh cli will be added to generate the parsed resources that will be stored by OpenCGA in our URL.
[x] A migration script will be added to remove any global panel.

opencb / opencga