Follow up the changes in the previous commit with some minor improvements
to formatting, grammar, spelling, and wording.
* layers/+distributions/spacemacs-docker/README.org: Replace "+" with
"and".
* layers/+email/mu4e/README.org: Use full sentences in the comments in the
mu4e-alert example.
* layers/+intl/japanese/README.org: Use verbatim markers for names of
files, functions, packages, and variables. Capitalize "Linux".
* layers/+os/osx/README.org: Capitalize "Emacs", "Vim", and "Evil".
* layers/+os/osx/config.el (osx-command-as, osx-use-dictionary-app):
* layers/+os/osx/keybindings.el (spacemacs/system-is-mac): Improve
docstrings.
* layers/+readers/dash/README.org: Capitalize "API", "Helm", and "Ivy".
* layers/+spacemacs/spacemacs-defaults/config.el
(delete-by-moving-to-trash): Use full sentences in comment.
* layers/+spacemacs/spacemacs-defaults/funcs.el
(spacemacs/toggle-frame-fullscreen-non-native): Improve docstrings.
There was a edge case with the declaration of the `lsp` layer in `layers.el`
files.
The `hy` layer depends on the `python` layer which in turn depends on the `lsp`
layer if and only if the `python-backend` layer variable is set to `lsp`.
When the `hy` layer was declared first then it declares the `python` layer
without its layer variables, thus the `lsp` layer was not declared because the
`python-backend` variable was not set.
The fix is to gather all the layer dependencies and resolve them only after all
the used layers have been declared.
* new function `configuration-layer/declare-layer-dependencies`
* replace all calls to `configuration-layer/declare-layer` by the new function
except for distribution layers (we declare layer dependencies right away in
distribution layers)