Adopt alternative impl for mapping caps lock to ctrl/esc

With this implementation, we need way less code than what was previously
used in `better-caps-lock.lua`, and we won't need all these manual
mappings anymore:

  https://github.com/jasonrudolph/keyboard/blob/7e12648/hammerspoon/better-caps-lock.lua#L48-L88

Shout out to @arbelt and @jasoncodes for this implementation:

- https://gist.github.com/arbelt/b91e1f38a0880afb316dd5b5732759f1
- https://github.com/jasoncodes/dotfiles/blob/ac9f3ac/hammerspoon/control_escape.lua

🍻

hammerspoon/control-escape.lua

@@ -0,0 +1,43 @@
+-- Credit for this implementation goes to @arbelt and @jasoncodes 🙇⚡️😻
+--
+--   https://gist.github.com/arbelt/b91e1f38a0880afb316dd5b5732759f1
+--   https://github.com/jasoncodes/dotfiles/blob/ac9f3ac/hammerspoon/control_escape.lua
+
+send_escape = false
+last_mods = {}
+
+control_key_handler = function()
+  send_escape = false
+end
+
+control_key_timer = hs.timer.delayed.new(0.15, control_key_handler)
+
+control_handler = function(evt)
+  local new_mods = evt:getFlags()
+  if last_mods["ctrl"] == new_mods["ctrl"] then
+    return false
+  end
+  if not last_mods["ctrl"] then
+    last_mods = new_mods
+    send_escape = true
+    control_key_timer:start()
+  else
+    if send_escape then
+      hs.eventtap.keyStroke({}, "ESCAPE")
+    end
+    last_mods = new_mods
+    control_key_timer:stop()
+  end
+  return false
+end
+
+control_tap = hs.eventtap.new({hs.eventtap.event.types.flagsChanged}, control_handler)
+control_tap:start()
+
+other_handler = function(evt)
+  send_escape = false
+  return false
+end
+
+other_tap = hs.eventtap.new({hs.eventtap.event.types.keyDown}, other_handler)
+other_tap:start()

hammerspoon/init.lua

@@ -6,7 +6,7 @@ keyUpDown = function(modifiers, key)
   hs.eventtap.event.newKeyEvent(modifiers, key, false):post()
 end
 
-require('better-caps-lock')
+require('control-escape')
 require('delete-words')
 require('hyper')
 require('super')

karabiner/karabiner.json

@@ -19,7 +19,7 @@
             "name": "Default profile",
             "selected": true,
             "simple_modifications": {
-                "caps_lock": "f19",
+                "caps_lock": "left_control",
                 "right_option": "f17"
             },
             "virtual_hid_keyboard": {