Change. fs_scandir returns array of files and array of types.

```Lua
local files, path, types = uv.fs_scandir("./")
for i, file in ipairs(files) do
  print(path .. file, types[i])
end
```
Update README.md
Add. `file:pipe()` method to convert file to pipe.

```Lua
uv.fs_open("tst.txt", function(file, err)
  if err then return end
  local pipe = file:pipe()
  ...
end)
```
Merge branch 'master' of https://github.com/moteus/lua-lluv
Add. `lluv.utils` module.
Fix. utils.Queue.
Rewrite examples using lluv.utils module.
Fix. `handle:fileno()` method.
Merge branch 'master' of https://github.com/moteus/lua-lluv
Add. `Errors` function to util module
Add. Starting works on FTP client.
Update FTP example
Merge branch 'master' of https://github.com/moteus/lua-lluv
Add. ftp stor command.
Add. Support ltn12 source/sink to stor/retr command
Fix. stor command is correct pasv transaction.
Implement some commands for ftp client.
Add. rmd/dele/mtdm commands to ftp client.
Fix. [FTP] stor command use incorrect file name
Fix. Memcached client call callbacks when lost connection.
Update lluv.utils module.
Update ftp example.