UI/API changes

• CHANGE: TLS summary improvements in measurement details overview
• CHANGE: Add support for "Written Off" probes
• CHANGE: Added subquery errors display to DNS measurement detail results
• FIX: http, ntp and ping rtt sorting in measurements detail results
• TWEAK: Make multi tabbed pages wrap on small screens
• TWEAK: Rework coverage map overlay legend
• TWEAK: Rename every instance of SSL to TLS