[fix] Fix ls(eggs) tests

Depending on the test environment, pip, setuptools and wheel dists
may be installed as .egg or .egg-link and may be files or folders.

src/zc/buildout/tests/buildout.txt

@@ -54,10 +54,11 @@ The ``bin`` directory contains scripts::
 
 The ``eggs`` directory has installed distributions:
 
-    >>> ls(sample_buildout, 'eggs')
-    -  pip.egg-link
-    -  setuptools.egg-link
-    -  wheel.egg-link
+    >>> print_() or ls(sample_buildout, 'eggs')
+    <BLANKLINE>
+    ...pip...
+    ...setuptools...
+    ...wheel...
     -  zc.buildout.egg-link
 
 The ``develop-eggs`` and ``parts`` directories are initially empty::
@@ -3171,11 +3172,12 @@ We also get other buildout artifacts::
     >>> ls(sample_bootstrapped, 'bin')
     -  buildout
 
-    >>> _ = (ls(sample_bootstrapped, 'eggs'),
+    >>> _ = (print_() or ls(sample_bootstrapped, 'eggs'),
     ...      ls(sample_bootstrapped, 'develop-eggs'))
-    -  pip.egg-link
-    -  setuptools.egg-link
-    -  wheel.egg-link
+    <BLANKLINE>
+    ...pip...
+    ...setuptools...
+    ...wheel...
     -  zc.buildout.egg-link
 
 (We list both the ``eggs`` and ``develop-eggs`` directories because the

src/zc/buildout/tests/test_all.py

@@ -1006,10 +1006,10 @@ On the other hand, if we have a zipped egg, rather than a develop egg:
     -  zc.recipe.egg.egg-link
 
     >>> ls('eggs') # doctest: +ELLIPSIS
-    -  foox-0.0.0-py2.4.egg
-    -  pip.egg-link
-    -  setuptools.egg-link
-    -  wheel.egg-link
+    -  foox-0.0.0-pyN.N.egg
+    ...pip...
+    ...setuptools...
+    ...wheel...
     -  zc.buildout.egg-link
 
 We do not get a warning, but we do get setuptools included in the working set: