UI/API changes

• NEW: Probes listing page
• CHANGE: Old probes listing page moved to legacy (in menu)
• CHANGE: Added search field to API keys
• CHANGE: Anchor Map no longer clusters point, shows all
• CHANGE: Measurement form API spec format for header key
• CHANGE: Horizontal scrolling arrow for wide tables
• FIX: Various formatting fixes
• FIX: Measurement form end date pick when no start date specified
• FIX: header app menu highlighting wrong app