Improved new system wizard

[deardooley]

The existing system addition wizard is a little overwhelming. Users should be able to add a new system with sensible defaults by specifying just the required features. This probably calls for different, streamlined "Add Compute" and "Add Storage" wizards. Minimal set of fields includes:

• System Type: grid of protocol badges.
• Name: a username-qualified id for the system (ex. user picks S3, systemId is -S3. Check for system id availability right away.)
• Host/endpoint + port: basic connectivity info. This would be unnecessary for some services like DropBox and Box.com, but necessary for others like Enterprise Box, SFTP, S3, OwnCloud, etc.
• Credentials: prompt the user for the correct credentials for the given protocol. In the case of cloud and GSI auth, the auth flow should be walked as part of the onboarding process.
• Verify: check the credentials immediately by accessing the system. Prompting the user to fix them if auth failed or show a confirmation message and a link to "browse data", "run code", "invite collaborators", or "set up alerts".