Fixed some smaller things in the docs

Author: mitsuhiko

docs/appcontext.rst

@@ -1,4 +1,4 @@
-.. _app_context:
+.. _app-context:
 
 The Application Context
 =======================

docs/reqcontext.rst

@@ -6,7 +6,7 @@ The Request Context
 This document describes the behavior in Flask 0.7 which is mostly in line
 with the old behavior but has some small, subtle differences.
 
-It is recommended that you read the :api:`app-context` chapter first.
+It is recommended that you read the :ref:`app-context` chapter first.
 
 Diving into Context Locals
 --------------------------

flask/__init__.py

@@ -25,7 +25,7 @@
     get_template_attribute, make_response, safe_join
 from .globals import current_app, g, request, session, _request_ctx_stack, \
      _app_ctx_stack
-from .ctx import has_request_context
+from .ctx import has_request_context, has_app_context
 from .module import Module
 from .blueprints import Blueprint
 from .templating import render_template, render_template_string