emacs: elgot and eldoc

[aemogie]

• use eldoc-box (eldoc in child frame)
• make eldoc show docstrings for elisp
• setup eglot to auto enable
  • prog-mode-hook that checks current major-mode in eglot-server-programs and sees if executable-find give non-nil, and if so runs eglot (if it doesnt just work, call-interactively)?