Add context-cleanups and fixture concept.

Context-cleanup:
Use context.add_cleanup(cleanup_func) to perform cleanups at end of scenario,
feature or test-run (depending on which context-layer the cleanup was added).
Cleanups are performed when current context-layer is removed.

Fixtures:
Simplify setup/cleanup tasks for scenario, feature or test-run.
A fixture basically provides a scope-guard
(similar to: @contextlib.contextmanager, @pytest.fixture).

CHANGES.rst

@@ -40,6 +40,8 @@ SITE:
 
 ENHANCEMENTS:
 
+  * fixtures: Add concept to simplify setup/cleanup tasks for scenario/feature/test-run
+  * context-cleanups: Use context.add_cleanup() to perform cleanups after scenario/feature/test-run.
   * Tagged Examples: Examples in a ScenarioOutline can now have tags.
   * pull  #447: behave settings from tox.ini (provided by: bittner)
   * issue #411: Support multiple active-tags with same category (submitted by: Kani999)

PROJECT_INFO.rst

@@ -1,21 +1,24 @@
 Project Info
 ===============================================================================
 
-=============== ===============================================================
+=============== ===================================================================
 Category        Hyperlink
-=============== ===============================================================
-Documentation:  http://pythonhosted.org/behave/
-                (or: http://behave.readthedocs.org/ for latest and stable)
+=============== ===================================================================
+Documentation:  http://behave.readthedocs.io/ for `latest`_ and `stable`_ (`PDF`_)
 Download:       http://pypi.python.org/pypi/behave (or: `github archive`_)
 Development:    https://github.com/behave/behave
 Issue Tracker:  https://github.com/behave/behave/issues
 Changelog:      `CHANGES.rst <CHANGES.rst>`_
 Newsgroup:      https://groups.google.com/forum/#!forum/behave-users
-=============== ===============================================================
+=============== ===================================================================
 
 .. hint::
 
     The PyPI version is the latest stable version.
     Otherwise, use the latest stable tag or the "bleeding edge" from Github.
 
+.. _latest: http://behave.readthedocs.io/en/latest/
+.. _stable: http://behave.readthedocs.io/en/stable/
+.. _PDF:    https://media.readthedocs.org/pdf/behave/latest/behave.pdf
+
 .. _`github archive`: https://github.com/behave/behave/tags

behave/__init__.py

@@ -19,11 +19,13 @@
 from __future__ import absolute_import
 from behave.step_registry import *      # pylint: disable=wildcard-import
 from behave.matchers import use_step_matcher, step_matcher, register_type
+from behave.fixture import fixture, use_fixture
 
 # pylint: disable=undefined-all-variable
 __all__ = [
     "given", "when", "then", "step", "use_step_matcher", "register_type",
     "Given", "When", "Then", "Step",
+    "fixture", "use_fixture",
     # -- DEPRECATING:
     "step_matcher"
 ]