Use nvim_ui_attach/nvim_ui_detach (#345)
Use nvim_ui_attach/nvim_ui_detach (#345)

* Use nvim_ui_attach/nvim_ui_detach

`ui_attach` and `ui_detach` are deprecated.

This handles the old signature, and issues a DeprecationWarning itself
then.

* fixup! Use nvim_ui_attach/nvim_ui_detach

neovim/python-client,zchee/python-client,zchee/python-client,Shougo/python-client,neovim/python-client,Shougo/python-client