v1.4.0

• New crawlers
• Fixed old GPX tracks from gulliver.it
• Fixed wrong competitions URLs
• Updated Mapbox SDK
• Added shareable URL for the map position
• Added shareable URLs for the contents
• Added user sign-in / sign-out via Facebook
• Improved user preferences (language, unit measure)
• Added a local history of recently opened locations
• Created a stories section (that will be soon populated) and a first story about italian parks
• Code cleanup and improved performances
• CSS and UI minor fixes