Python-telegram-bot

- Emoji class now uses bytes_to_native_str from future 3rd party lib (92)
- Make user_from optional to work with channels channels (91)
- Raise exception if Telegram times out on long-polling (90)

_Special thanks to jh0ker for all hard work_

- Type as optional for GroupChat class

- Adds type to User and GroupChat classes (pre-release Telegram feature)

- Handles HTTP Bad Gateway (503) errors on request (63)
- Fixes regression on Audio and Document for unicode fields (65)

- getFile and File.download is now fully supported (69)

- Moved Bot._requestURL to its own class (telegram.utils.request)
- Much better, such wow, Telegram Objects tests
- Add consistency for str properties on Telegram Objects
- Better design to test if chat_id is invalid
- Add ability to set custom filename on Bot.sendDocument(..,filename='') (56)
- Fix Sticker as InputFile
- Send JSON requests over urlencoded post data (58)
- Markdown support for Bot.sendMessage(..., parse_mode=ParseMode.MARKDOWN) (58)
- Refactor of TelegramError class (no more handling IOError or URLError)