Better error management

[shawninder]

• Add error handling everywhere
• Make sure all message tell the end-users (users and dev alike) what to do, in addition to hinting at what went wrong
• Make sure all unexpected behaviour (crashes, unhandled exceptions, unexpected hangups, etc.) is logged along with the appropriate meta-data (time&date, service, logged in user and device info, relevant context, etc.)
• Implement a dismissable 404 popup (rather than a 404 page)