Document the global :LuaCheckSyntax and :LuaCheckGlobals commands
Make name/path of Lua interpreter configurable
Add parentheses to functions in overview of known globals
Improve interaction between automatic syntax/globals checks
Try to resolve pull request #23 (workaround for table indexes in globals.lua)

See pull request #23 on GitHub:
  https://github.com/xolox/vim-lua-ftplugin/pull/23