Add luvit implementations for echo & http servers

Since we are comparing nodejs and its uv bindings, it would be
interesting to see how lua's libuv bindings compare.

Author: rgrinberg

servers/luvit_http_server.lua

@@ -0,0 +1,23 @@
+local http = require('http')
+local url = require('url')
+
+responses = {}
+
+http.createServer(function (req, res)
+  req.uri = url.parse(req.url)
+  local msize = 1024
+  local path = req.uri.pathname
+  if string.len(path) > 1 then
+    msize = tonumber(string.sub(path, 2))
+  end
+
+  if not responses[msize] then
+    responses[msize] = string.rep("X", msize)
+  end
+
+  res:setHeader("Content-Type", "text/plain")
+  res:setHeader("Content-Length", msize)
+  res:finish(responses[msize])
+end):listen(25000, '127.0.0.1')
+
+print('Server running at http://127.0.0.1:25000/')

servers/luvitecho.lua

@@ -0,0 +1,27 @@
+local uv = require('uv')
+
+-- Create listener socket
+local server = uv.new_tcp()
+server:bind('127.0.0.1', 25000)
+
+server:listen(128, function(err)
+  -- Create socket handle for client
+  local client = uv.new_tcp()
+
+  -- Accept incoming connection
+  server:accept(client)
+
+  -- Relay data back to client
+  client:read_start(function(err, data)
+    if err then
+      client:close()
+      return
+    end
+
+    if data then
+      client:write(data)
+    else
+      client:close()
+    end
+  end)
+end)