Refactor and simplify dicts

- frontend.dicts encapsulates dicts behavior for all other namespaces
- Each dict ns only has one var which prepares us
- No longer need shortcut.dicts
- Fix remaining lints that were broken
- Also bring back frontend.dicts
- Update guide
- Add a false binding to :editor/toggle-undo-redo-mode which throws a
  needless warning

src/main/frontend/context/i18n.cljs

@@ -2,13 +2,11 @@
   "This ns is a system component that handles translation for the entire
   application. The ns dependencies for this ns must be small since it is used
   throughout the application."
-  (:require [frontend.dicts.core :as dicts]
-            [frontend.modules.shortcut.dicts :as shortcut-dicts]
+  (:require [frontend.dicts :as dicts]
             [tongue.core :as tongue]
             [frontend.state :as state]))
 
-(def dicts
-  (merge-with merge dicts/dicts shortcut-dicts/dicts))
+(def dicts (merge dicts/dicts {:tongue/fallback :en}))
 
 (def translate
   (tongue/build-translate dicts))