patch 8.0.1390: DirectX scrolling can be slow, vertical positioning is off commit https://github.com/vim/vim/commit/7f88b65f6cde3d69386e461f61271a271b79b7e8 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Dec 14 13:15:19 2017 +0100 patch 8.0.1390: DirectX scrolling can be slow, vertical positioning is off Problem: DirectX scrolling can be slow, vertical positioning is off. Solution: Make scroll slightly faster when using "scrlines:1". Fix y position of displayed text. Fix DirectX with non-utf8 encoding. (Ken Takata, closes #2440)

This is a MODIFIED version of libvterm.

The original can be found:
- on the original site (tar archive and Bazaar repository):
	http://www.leonerd.org.uk/code/libvterm/
- cloned on Github:
	https://github.com/neovim/libvterm

Modifications:
- Add a .gitignore file.
- Convert from C99 to C90.
- Other changes to support embedding in Vim.