improve --markers output

CHANGELOG

@@ -8,6 +8,9 @@ Changes between 2.3.0 and 2.3.dev
 - skip pexpect using tests (test_pdb.py mostly) on freebsd* systems
   due to pexpect not supporting it properly (hanging)
 
+- link to web pages from --markers output which provides help for
+  pytest.mark.* usage.
+
 Changes between 2.2.4 and 2.3.0
 -----------------------------------
 

_pytest/python.py

@@ -110,10 +110,12 @@ def pytest_configure(config):
         "times passing in multiple different argument value sets. Example: "
         "@parametrize('arg1', [1,2]) would lead to two calls of the decorated "
         "test function, one with arg1=1 and another with arg1=2."
+        " see http://pytest.org/latest/parametrize.html for more info and "
+        "examples."
     )
     config.addinivalue_line("markers",
         "usefixtures(fixturename1, fixturename2, ...): mark tests as needing "
-        "all of the specified fixtures."
+        "all of the specified fixtures. see http://pytest.org/latest/fixture.html#usefixtures "
     )
 
 def pytest_sessionstart(session):

_pytest/skipping.py

@@ -14,7 +14,8 @@ def pytest_configure(config):
         "skipif(*conditions): skip the given test function if evaluation "
         "of all conditions has a True value.  Evaluation happens within the "
         "module global context. Example: skipif('sys.platform == \"win32\"') "
-        "skips the test if we are on the win32 platform. "
+        "skips the test if we are on the win32 platform. see "
+        "http://pytest.org/latest/skipping.html"
     )
     config.addinivalue_line("markers",
         "xfail(*conditions, reason=None, run=True): mark the the test function "
@@ -22,6 +23,7 @@ def pytest_configure(config):
         "if you don't even want to execute the test function. Any positional "
         "condition strings will be evaluated (like with skipif) and if one is "
         "False the marker will not be applied."
+        "see http://pytest.org/latest/skipping.html"
     )
 
 def pytest_namespace():