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/index.html

@@ -19,7 +19,7 @@
     <app-root>
         <div class="mt-5 d-flex justify-content-center">
             <div>
-                <img src="./images/logo-dark@2x.png" class="mb-4 logo" alt="Bitwarden">
+                <div id="loginLogo" class="mb-4 logo" alt="Bitwarden"></div>
                 <p class="text-center">
                     <i class="fa fa-spinner fa-spin fa-2x text-muted" title="Loading" aria-hidden="true"></i>
                 </p>