Change windows packager to download and install latest plugins

setup.py

@@ -419,7 +419,7 @@ try:
             # cannot use super() with old-style parent class
             babel.extract_messages.initialize_options(self)
             self.output_file = 'po/picard.pot'
-            self.input_dirs = 'picard'
+            self.input_dirs = 'contrib, picard'
             if self.input_dirs and input_dirs_workaround:
                 self._input_dirs = self.input_dirs
 
@@ -665,6 +665,22 @@ def generate_file(infilename, outfilename, variables):
             f_out.write(f_in.read() % variables)
 
 
+def contrib_plugin_files():
+    plugin_files = {}
+    dist_root = os.path.join("contrib", "plugins")
+    for root, dirs, files in os.walk(dist_root):
+        file_root = os.path.join('plugins', os.path.relpath(root, dist_root)) \
+            if root != dist_root else 'plugins'
+        for file in files:
+            if file.endswith(".py"):
+                if file_root in plugin_files:
+                    plugin_files[file_root].append(os.path.join(root, file))
+                else:
+                    plugin_files[file_root] = [os.path.join(root, file)]
+    data_files = [(x, sorted(y)) for x, y in plugin_files.iteritems()]
+    return sorted(data_files, key=lambda x: x[0])
+
+
 try:
     from py2exe.build_exe import py2exe
 
@@ -684,6 +700,7 @@ try:
                                   find_file_in_path("PyQt4/plugins/imageformats/qtiff4.dll")]))
             self.distribution.data_files.append(
                 ("accessible", [find_file_in_path("PyQt4/plugins/accessible/qtaccessiblewidgets4.dll")]))
+            self.distribution.data_files += contrib_plugin_files()
 
             py2exe.run(self)
             print("*** creating the NSIS setup script ***")