Commit Briefs
add backspace (keycode 127), for the linux tty
linux ttys seems to send 127 on backspace, or at least do that under tmux. Educate telescope to treat 127 as del.
big refactor: introduce the window abstraction
- commands now take a struct window* instead of a raw tab - the struct ui_state is gone - using a window for the minibuffer too helps avoid code duplication - it will let us having more than one window on a tab! :DD It doesn't seem to have broken anything...
fix various warnings, no functional changes
now that we have a bounch of -Wxxx flags during compilation, let's fix everything.