Adds a storage wrapper system, as well as a new filesystem
based storage implementation to be called from it.
Adds new persistence implementation of the web services
portion of listing save states using the newly added
storage system.

Fixes #2750.
Adds the rsvp.js library to provide a Promises/A+ interface.
Adds the initial vwf/admin.js javascript module for providing
outside of the application context functionality.
Adds the getSaveState and application.getSaveState functions
to the new vwf/admin.js module.

Fixes #2747.
Removes stray debug message.

References #2750.