1. disable filetype plugin;
2. add import into beta.py augroup;
3. add ++nested for BufEnter,
but at the end, just disable filetype
plugin;
since can't figure out the way
to override its effect;
1. handle escape character;
2. handle items filtering
based on entered letters;
3. redraw UI when the filter
changes;
4. TODO
handle selection changes via arrows, hjkl;
5. TODO
handle selection after Enter has been pressed;