Implement :BuildDir and :Build commands in Lua

Ported over from and improved for best integration with Neovim ecosystem
https://code.infektor.net/config/vim/src/branch/master/autoload/build.vim

init.lua

@@ -2,6 +2,7 @@ require('settings')
 require('mappings')
 require('netrw')
 require('autocmds')
+require('build')
 
 local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"
 if not vim.loop.fs_stat(lazypath) then