Import TheBB configuration into Spacemacs and add `C-S-h` to replace
redefined `C-h` binidng.
Also remove the go up a directory behavior on backspace, now backspace
is a regular backspace.
Put the toggles on SPC t E with
SPC t E h -> holy-mode
SPC t E y -> hybrid-mode
Make the mode-line diminished lighter consistent with the key bindings,
so holy is Ⓔh and hybrid is Ⓔy
Add seamless switch between holy and hybrid.
This is how evil-leader gets `SPC m` to work for mode specific bindings,
and we need to mirror this step for `M-m`. This is big change, but in
order for `M-m` to work properly we need to remap it to the mode-map
whenever possible.
