1.8.1

• Added optionnal tunneling feature (not fully compatible with Jump Point Search as of now)
• Fixed path request failure when stepping from an unwalkable location
• Fixed getPath() to keep continuously failing right after an wrong path request
• Fixed _PATH for compatibility with handheld devices
• Added handling for nil values pushed into heaps
• Added Node as a syntactic shortcut to Node:new(...)
• Added type & validity checking for grid objects
• Added type & validity checking for passed-in maps
• Changed pathfinder initialization args order
• PathFinder:setFinder() now handles nil
• New implementation of Astar, reused internally for Dijkstra Algorithm
• Added Telescope specs tests
• Added Travis-CI validation