docs(sce,urlutils): update table to use marked syntax

Commit 258cae8 replaced Showdown with marked.

Author: chirayuk

src/ng/sce.js

@@ -456,7 +456,7 @@ function $SceDelegateProvider() {
  * ## What trusted context types are supported?<a name="contexts"></a>
  *
  * | Context             | Notes          |
- * |=====================|================|
+ * |---------------------|----------------|
  * | `$sce.HTML`         | For HTML that's safe to source into the application.  The {@link ng.directive:ngBindHtml ngBindHtml} directive uses this context for bindings. |
  * | `$sce.CSS`          | For CSS that's safe to source into the application.  Currently unused.  Feel free to use it in your own directives. |
  * | `$sce.URL`          | For URLs that are safe to follow as links.  Currently unused (`<a href=` and `<img src=` sanitize their urls and don't consititute an SCE context. |

src/ng/urlUtils.js

@@ -58,15 +58,15 @@ function $$UrlUtilsProvider() {
      * Otherwise, returns an object with the following members.
      *
      *   | member name   | Description    |
-     *   |===============|================|
+     *   |---------------|----------------|
      *   | href          | A normalized version of the provided URL if it was not an absolute URL |
      *   | protocol      | The protocol including the trailing colon                              |
      *   | host          | The host and port (if the port is non-default) of the normalizedUrl    |
      *
      * These fields from the UrlUtils interface are currently not needed and hence not returned.
      *
      *   | member name   | Description    |
-     *   |===============|================|
+     *   |---------------|----------------|
      *   | hostname      | The host without the port of the normalizedUrl                         |
      *   | pathname      | The path following the host in the normalizedUrl                       |
      *   | hash          | The URL hash if present                                                |