Now the user should use `SPC f e h` helm-spacemacs.
This is due to the fact that spacemacs layer is now a regular layer
stored in the "layers" directory.
- Rename contrib directory to layers
- Add new variable dotspacemacs-distribution
- Move spacemacs layer to layers/!distribution
- New layer spacemacs-core in layers/!distribution
- User can now set dotspacemacs-distribution to spacemacs or
spacemacs-core (default spacemacs)
spacemacs-core is very lightweight layer sufficient to build upon
spacemacs.
