frontends (jp/blog), plugin blog_import: fixes:

- argparse argument with nargs > 1 and default == {} crashes when reading the user input
    - separate blog import options with a new line
    - convert DBus strings received by the backend to unicode

src/plugins/plugin_blog_import.py

@@ -94,12 +94,13 @@ class BlogImportPlugin(object):
 
     def _blogImport(self, name, location, options, pubsub_service='', profile=C.PROF_KEY_DEFAULT):
         client = self.host.getClient(profile)
+        options = {key: unicode(value) for key, value in options.iteritems()}
         for option in BOOL_OPTIONS:
             try:
                 options[option] = C.bool(options[option])
             except KeyError:
                 pass
-        return self.blogImport(client, name, location, options)
+        return self.blogImport(client, unicode(name), unicode(location), options)
 
     @defer.inlineCallbacks
     def blogImport(self, client, name, location, options=None, pubsub_service=None):