[svn r58308] * de-generalize conditional skips and only care

nicely for common tedious causes of skipping:
  import a module and checking it has a certain
  version.  usage example:

  docutils = py.test.importorskip(docutils, minversion="0.4")

* used new helper and cleanup skipping logic in py lib

--HG--
branch : trunk

py/path/svn/testing/test_urlcommand.py

@@ -1,13 +1,12 @@
 import py
 from py.__.path.svn.urlcommand import InfoSvnCommand
 from py.__.path.svn.testing.svntestbase import CommonCommandAndBindingTests, \
-                                               getrepowc
+                                               getrepowc, getsvnbin
 import datetime
 import time
 
 def setup_module(mod):
-    if py.path.local.sysfind('svn') is None:
-        py.test.skip("cannot test py.path.svn, 'svn' binary not found")
+    getsvnbin()
 
 class TestSvnURLCommandPath(CommonCommandAndBindingTests):
     def setup_class(cls):