Majorly re-organize modules

- Split large modules into smaller parts (e.g. siren-text-manipulation)
- Organize modules into high level groups:
  - completion
  - core
  - editor
  - languages
  - linting
  - misc
  - navigation
  - projects
  - spelling
  - text-editing
  - version-control
  - windows
  - workspaces

modules/workspaces/siren-workgroups2.el

@@ -0,0 +1,14 @@
+;;; siren-workgroups2.el --- jimeh's Emacs Siren: workgroups2 configuration.
+
+;;; Commentary:
+
+;; Basic configuration for workgroups2.
+
+;;; Code:
+
+(use-package workgroups2
+  :config
+  (setq wg-prefix-key (kbd "C-z")))
+
+(provide 'siren-workgroups2)
+;;; siren-workgroups2.el ends here