Pass match rather than pattern argument to files()

The pattern argument to listdir() has been deprecated in favor of the
match argument. They don't function in the exact same way as match
expects a callable that will be used for matching.

tests/test_distribution.py

@@ -2,7 +2,7 @@
 import os
 import pytest
 
-from path import Path
+from path import Path, matchers
 
 DIST_DIR = os.path.abspath(os.path.join(os.path.dirname(__file__), '../dist'))
 
@@ -18,7 +18,7 @@ def _check_ninja_install(virtualenv):
 
 @pytest.mark.skipif(not Path(DIST_DIR).exists(), reason="dist directory does not exist")
 def test_source_distribution(virtualenv):
-    sdists = Path(DIST_DIR).files(pattern="*.tar.gz")
+    sdists = Path(DIST_DIR).files(match=matchers.CaseInsensitive("*.tar.gz"))
     if not sdists:
         pytest.skip("no source distribution available")
     assert len(sdists) == 1
@@ -32,7 +32,7 @@ def test_source_distribution(virtualenv):
 
 @pytest.mark.skipif(not Path(DIST_DIR).exists(), reason="dist directory does not exist")
 def test_wheel(virtualenv):
-    wheels = Path(DIST_DIR).files(pattern="*.whl")
+    wheels = Path(DIST_DIR).files(match=matchers.CaseInsensitive("*.whl"))
     if not wheels:
         pytest.skip("no wheel available")
     assert len(wheels) == 1