Simple wrapper around LuaSocket ftp.
##Usage
local ftp = require "ftp"
local f = ftp.new{
host = '127.0.0.1',
uid = 'moteus',
pwd = '12345',
}
assert(f:noop())
for _, info in ipairs(f:list()) do print(info) end
f:cd('some/sub/dir')
-- upload data
f:put_data('test.txt', 'this is test message')
-- download file
f:get_file('test.txt', './local/path/test.txt')
##Dependences##