grappling hook

tech grappling hook - can attack to walls and pull you towards the walls
   harpoon extends farther as you hold down fire, but no longer has auto-steering

mobs do 4% less harm per difficulty level
railgun/harpoon auto-targeting is smarter at long distances with multiple small targets
  but it still has trouble with moving targets
booby trap only has a 100 -> 50% chance to drop a mine when picking up power ups
added fallback for browsers that don't allow local storage

js/powerup.js

@@ -872,7 +872,7 @@ const powerUps = {
         powerUps.research.currentRerollCount = 0
         if (tech.isTechDamage && who.name === "tech") m.damage(0.11)
         if (tech.isMassEnergy) m.energy += 2;
-        if (tech.isMineDrop && bullet.length < 150) {
+        if (tech.isMineDrop && bullet.length < 150 && Math.random() < 0.66) {
             if (tech.isLaserMine && input.down) {
                 b.laserMine(who.position)
             } else {