Add lua support through local-lua-debugger-vscode

Add the lua adapter to gadgets.py and installer.py, update the README.md
file and create basic tests using lua, luajit and love.

support/test/lua/simple/.vimspector.json

@@ -0,0 +1,29 @@
+{
+  "$schema": "https://puremourning.github.io/vimspector/schema/vimspector.schema.json#",
+  "configurations": {
+    "lua": {
+      "adapter": "lua-local",
+      "configuration": {
+        "request": "launch",
+        "type": "lua-local",
+        "cwd": "${workspaceFolder}",
+        "program": {
+          "lua": "lua",
+          "file": "simple.lua"
+        }
+      }
+    },
+    "luajit": {
+      "adapter": "lua-local",
+      "configuration": {
+        "request": "launch",
+        "type": "lua-local",
+        "cwd": "${workspaceFolder}",
+        "program": {
+          "lua": "luajit",
+          "file": "simple.lua"
+        }
+      }
+    }
+  }
+}

support/test/lua/simple/simple.lua

@@ -0,0 +1,25 @@
+if pcall(require, 'lldebugger') then
+  require('lldebugger').start()
+end
+
+local separator = ' '
+
+
+local function createMessage()
+  local words = {}
+  table.insert(words, 'Hello')
+  table.insert(words, 'world')
+  return table.concat(words, separator)
+end
+
+
+local function withEmphasis(func)
+  return function()
+    return func() .. '!'
+  end
+end
+
+
+createMessage = withEmphasis(createMessage)
+
+print(createMessage())