Hide properties in space-doc-mode to allow the use of `CUSTOM_ID` tags in
documentation for correct link exporting, as discussed in #8054, #8136
and #8138. Complementary the latter two PR:s.
Prevent next-buffer, other-buffer, etc. from choosing useless buffers.
No need for spacemacs/next-useful-buffer,
spacemacs/previous-useful-buffer anymore.
Also fix spacemacs/alternate-buffer to respect buffer-predicate.
When spacemacs-layouts is used, buffer-predicate filters useful buffer
that belong to the current layout.
- move evil-org to org layer
- move org-plus-contrib to spacemacs-org layer
- remove toc-org from the list of package for org layer
- give ownership of the org package to org layer
- invent a package named default-org in spacemacs-org layer in order
to let the ownership of org package to org layer
- remove unnecessary :mode keyword in use-package from for org