Move script to download pages out of tests_lyrics.py

By default (as runned by CI tools), only *fake* example.com page is present in
rsr/lyrics and tests that check content of pages coming from *real* sources are
thus skipped.
Execute lyrics_download_samples.py to download pages from *real* sources. When
done and *real* pages are present on disk, no tests are skipped.

test/lyrics_download_samples.py

@@ -0,0 +1,54 @@
+# This file is part of beets.
+# Copyright 2014, Fabrice Laporte
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+
+import os
+import sys
+import requests
+
+import test_lyrics
+
+
+def mkdir_p(path):
+    try:
+        os.makedirs(path)
+    except OSError:
+        if os.path.isdir(path):
+            pass
+        else:
+            raise
+
+
+def safe_open_w(path):
+    ''' Open "path" for writing, creating any parent directories as needed.
+    '''
+    mkdir_p(os.path.dirname(path))
+    return open(path, 'w')
+
+
+def main(argv=None):
+    """download"""
+
+    if argv is None:
+        argv = sys.argv
+
+    for s in test_lyrics.SOURCES:
+        url = s['url'] + s['path']
+        fn = test_lyrics.url_to_filename(url)
+        if not os.path.isfile(fn):
+            html = requests.get(url).text
+            with safe_open_w(fn) as f:
+                f.write(html.encode('utf8'))
+
+if __name__ == "__main__":
+    sys.exit(main())

test/test_lyrics.py

@@ -172,22 +172,6 @@ def url_to_filename(url):
     return fn
 
 
-def mkdir_p(path):
-    try:
-        os.makedirs(path)
-    except OSError:
-        if os.path.isdir(path):
-            pass
-        else:
-            raise
-
-
-def safe_open_w(path):
-    ''' Open "path" for writing, creating any parent directories as needed.
-    '''
-    mkdir_p(os.path.dirname(path))
-    return open(path, 'w')
-
 
 class MockFetchUrl(object):
     def __init__(self, pathval='fetched_path'):
@@ -282,14 +266,6 @@ SOURCES = [
 ]
 
 
-def download_source_sample(url):
-    fn = url_to_filename(url)
-    if not os.path.isfile(fn):
-        html = requests.get(url).text
-        with safe_open_w(fn) as f:
-            f.write(html.encode('utf8'))
-
-
 class LyricsGooglePluginTest(unittest.TestCase):
     """Test scraping heuristics on a fake html page.
     Use `nosetests -s test_lyrics.py -a '!slow'` to check that beets google