Import vim runtime from changeset 5697:c2098c3095e7

This includes all files present in the original runtime/ tree. Subsequent
commits will clean cruft out.
Remove tools/
Remove .info files
Delete images and related files
Remove doc/

Documentation resides at https://github.com/neovim/docs
Merge pull request #3 from neovim/init-import

[RDY] Clean initial import