Partially revert previous commit (remove file-urlmd5-exclude option)

We want buildout to cache as many things as possible.

This partially reverts commit 10478e98.

src/zc/buildout/buildout.py

@@ -525,13 +525,6 @@ class Buildout(DictMixin):
             except Exception:
                 self._logger.exception(
                     "Failed to setup Networkcache. Continue without.")
-            else:
-                networkcache_client._buildout_download_filter = match_list = []
-                for pattern in networkcache_section.get('file-urlmd5-exclude',
-                                                        '').split():
-                    include = pattern.startswith('!')
-                    match_list.append((not include,
-                        re.compile(pattern[include:]).match))
 
     def _buildout_path(self, name):
         if '${' in name:

src/zc/buildout/download.py

@@ -300,9 +300,7 @@ class Download(Download):
     def _download(self, url, path, md5sum=None, alternate_url=None):
         from .buildout import networkcache_client as nc
         while nc: # not a loop
-            if (self._auth(url) # do not cache restricted data
-                or next((x for x, match in nc._buildout_download_filter
-                           if match(url)), False)):
+            if self._auth(url): # do not cache restricted data
                 nc = None
                 break
             key = 'file-urlmd5:' + md5(url.encode()).hexdigest()