Repository Monitoring settings page

[andrew]

Move the current /dashboard UI into a separate page for configuring which repositories should be monitored by Libraries, more like a settings interface than a homepage.

• Show last_synced_at, sync status and sync button
• Ajax toggle watch button
• Slimline GitHub repo partial
• Show current selected org
• Sorting options for repositories
• Search repos
• Show repository count for orgs
• Show repos you don't have webhook access as disabled
• Link to manage org access, similar to travis https://github.com/settings/connections/applications/#{GITHUB_KEY}
• Expand to see dependencies

[andrew]

Moving this to the Backlog as we'd still like to implement it but can't see that happening in the near future.