Theme Support with a Dark Mode (#974)

* Stylesheets

* Theme Configuration

* Options Area

* swal2 style

Missed the swal2 styling and improved the table theming

* Icon styling

* Fix theme not saving

* Update English

Remove colour to make it more translatable between English and American

* Update messages.json

* Login logo

* dropdown and login logo

* btn-link and totp fix

Added a border for extra readability on the btn-link

* Organisation Styling

* Update messages.json

* Update webauthn-fallback.ts

Add missing semicolon and enable console.error bypass for tslint

* Fix contrast issues

Update the blue to match the browser extension and lighten the grey for text-muted variable

* Add Paypal Container and Loading svg file

* Update jslib

* Password Generator contrast fix

src/images/loading-white.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="100%" height="100%" viewBox="0 0 100% 100%">
+  <text fill="#fbfbfb" x="50%" y="50%" font-family="\'Open Sans\', \'Helvetica Neue\', Helvetica, Arial, sans-serif"
+        font-size="18" text-anchor="middle">
+    Loading...
+  </text> 
+</svg>

src/images/loading.svg

@@ -1,6 +1,6 @@
 <svg xmlns="http://www.w3.org/2000/svg" width="100%" height="100%" viewBox="0 0 100% 100%">
-  <text fill="%23333333" x="50%" y="50%" font-family="\'Open Sans\', \'Helvetica Neue\', Helvetica, Arial, sans-serif"
+  <text fill="#333333" x="50%" y="50%" font-family="\'Open Sans\', \'Helvetica Neue\', Helvetica, Arial, sans-serif"
         font-size="18" text-anchor="middle">
     Loading...
   </text>
-</svg>
+</svg>