refining examples and updating docs with actual output from examples

--HG--
branch : trunk

example/funcarg/costlysetup/conftest.py

@@ -0,0 +1,22 @@
+
+class ConftestPlugin:
+    def pytest_configure(self, config):
+        self._setup = None
+
+    def pytest_funcarg__setup(self, request):
+        if self._setup is None:
+            self._setup = CostlySetup()
+        return self._setup
+
+    def pytest_unconfigure(self, config):
+        if self._setup is not None:
+            self._setup.finalize()
+
+class CostlySetup:
+    def __init__(self):
+        import time
+        time.sleep(5)
+        self.timecostly = 1
+
+    def finalize(self):
+        del self.timecostly