refactor(ui): Refactor the keyboardLayouts (#497)

Add missing keyboard mappings for most layouts
Change  pasteModel.tsx to use the new structure and vastly clarified the way that keys are emitted.
Make each layout export just the KeyboardLayout object (which is a package of isoCode, name, and chars)
Made keyboardLayouts.ts export a function to select keyboard by `isoCode`, export the keyboards as label . value pairs (for a select list) and the list of keyboards.
Changed devices.$id.settings.keyboard.tsx use the exported keyboard option list.

ui/src/keyboardLayouts/fr_BE.ts

@@ -1,6 +1,6 @@
-import { KeyCombo } from "../keyboardLayouts"
+import { KeyboardLayout, KeyCombo } from "../keyboardLayouts"
 
-export const name = "Belgisch Nederlands";
+const name = "Belgisch Nederlands";
 
 const keyTrema = { key: "BracketLeft", shift: true } // tréma (umlaut), two dots placed above a vowel
 const keyHat = { key: "BracketLeft" } // accent circonflexe (accent hat), mark ^ placed above the letter
@@ -8,7 +8,7 @@ const keyAcute = { key: "Semicolon", altRight: true } // accent aigu (acute acce
 const keyGrave = { key: "Quote", shift: true } // accent grave, mark ` placed above the letter
 const keyTilde = { key: "Slash", altRight: true } // tilde, mark ~ placed above the letter
 
-export const chars = {
+const chars = {
   A: { key: "KeyQ", shift: true },
   "Ä": { key: "KeyQ", shift: true, accentKey: keyTrema },
   "Â": { key: "KeyQ", shift: true, accentKey: keyHat },
@@ -165,3 +165,9 @@ export const chars = {
   Enter: { key: "Enter" },
   Tab: { key: "Tab" },
 } as Record<string, KeyCombo>;
+
+export const fr_BE: KeyboardLayout = {
+  isoCode: "fr-BE",
+  name: name,
+  chars: chars
+};