I donated > 50 $, should be with URL

See; https://www.bountysource.com/people/24072-lsc
Added os_isatty
Removed mch_check_win
Removed mch_input_isatty
Replace explicit uv_guest_handle(fd) == UV_TTY by os_isatty
Remove 'textauto' option

For the same reason we removed 'textmode'.
Remove "h" flag of 'highlight' option

HLF_H is an obsolete flag and got replaced by HLF_E.
Add the -Wconversion flag for some files.

This is to provide some infrastructure to help with issue #567 (Enable
-Wconversion file by file).
Fix update of pending_reqs in `write_cb`
Refactor API types

Use specialized String/Array types that map more easily to msgpack
Add channel module

- Add channel module that exposes the API over arbitrary streams
- Add `xmemdup` for duplicating memory chunks
- Make job exit callback optional
Add server module for accepting API connections