chore(jade): upgrade to use marked filter

The `Transformers.markdown` (`:markdown`) filter is deprecated. This commit updates
the entire docs project to use the `jstransformer-marked` (`:marked') filter.

tools/api-builder/docs-package/processors/convertBackticksToCodeBlocks.js

@@ -49,7 +49,7 @@ module.exports = function convertBackticksToCodeBlocks() {
                 // modulo op in next line insures that pad is always a multiple of 2 ( jade whitespace).
                 postPad = postPad.substr(2 + (postPad.length % 2)); // exdent
               }
-              replaceVal = replaceVal + postPad + ':markdown\n';
+              replaceVal = replaceVal + postPad + ':marked\n';
             }
             doc.renderedContent = doc.renderedContent.replace(entireBlock, replaceVal);
             captures = BACKTICK_CAPTURE.exec(doc.renderedContent);

tools/api-builder/docs-package/processors/convertBackticksToCodeBlocks.spec.js

@@ -30,7 +30,7 @@ describe('convertBackticksToCodeBlocks', function() {
       'export class TypeScriptClass {\n' +
       '}\n' +
       '\n' +
-      ':markdown\n' +
+      ':marked\n' +
       'postamble\n'
     );
   });