Add more explanation for what escaping is (#10751)

* Update button text and Explain more what escaping is
Redirect back to settings page with flash message on success

challenges/01-front-end-development-certification/basic-javascript.json

@@ -1159,7 +1159,7 @@
       "id": "56533eb9ac21ba0edf2244b6",
       "title": "Escape Sequences in Strings",
       "description": [
-        "Quotes are not the only characters that can be <dfn>escaped</dfn> inside a string. Here is a table of common escape sequences:",
+        "Quotes are not the only characters that can be <dfn>escaped</dfn> inside a string. There are two reasons to use escaping characters: First is to allow you to use characters you might not otherwise be able to type out, such as a backspace. Second is to allow you to represent multiple quotes in a string without JavaScript misinterpreting what you mean. We learned this in the previous challenge.",
         "<table class=\"table table-striped\"><thead><tr><th>Code</th><th>Output</th></tr></thead><tbody><tr><td><code>\\'</code></td><td>single quote</td></tr><tr><td><code>\\\"</code></td><td>double quote</td></tr><tr><td><code>\\\\</code></td><td>backslash</td></tr><tr><td><code>\\n</code></td><td>newline</td></tr><tr><td><code>\\r</code></td><td>carriage return</td></tr><tr><td><code>\\t</code></td><td>tab</td></tr><tr><td><code>\\b</code></td><td>backspace</td></tr><tr><td><code>\\f</code></td><td>form feed</td></tr></tbody></table>",
         "<em>Note that the backslash itself must be escaped in order to display as a backslash.</em>",
         "<h4>Instructions</h4>",