Docserver: roll third_party/handlebar/handlebar.py and tiny server2 change to

chrome/common/extensions/docs/server2/template_renderer.py

Index: chrome/common/extensions/docs/server2/template_renderer.py
diff --git a/chrome/common/extensions/docs/server2/template_renderer.py b/chrome/common/extensions/docs/server2/template_renderer.py
index ab578db7b827bf1eaecc7a9e95c3a295441f0917..e63f77186772bed918970305e4af5dd807bb6c8f 100644
--- a/chrome/common/extensions/docs/server2/template_renderer.py
+++ b/chrome/common/extensions/docs/server2/template_renderer.py
@@ -25,10 +25,8 @@ class TemplateRenderer(object):
       'apps_samples_url': GITHUB_BASE,
       'base_path': server_instance.base_path,
       'extensions_samples_url': EXTENSIONS_SAMPLES,
-      'false': False,
       'samples': server_instance.samples_data_source_factory.Create(request),
       'static': server_instance.base_path + 'static',
-      'true': True,
     }
     render_context.update(CreateDataSources(server_instance, request=request))
     render_data = template.render(render_context)