more orbs in text

replaced tech, field, and gun text with orbs
  orbs length scale with px->em
cleaned up simulation variables text in pause menu
some minor tech description changes
total tech count no longer includes instant tech or removed tech

tech: planned obsolescence - at the start of each level eject your oldest tech and gain 1.1 damage

heuristics 1.3 -> between 1 and 1.5 fire rate
combinatorial optimization 1.35->1.4 damage

difficulty reduction per level
  0.85->0.87x damage done
  1.23->1.22 damage taken

js/simulation.js

@@ -830,6 +830,7 @@ const simulation = {
         simulation.wipe = function () { //set wipe to normal
             ctx.clearRect(0, 0, canvas.width, canvas.height);
         }
+        m.lastHit = 0
         m.hole.isOn = false
         simulation.paused = false;
         engine.timing.timeScale = 1;