小Bug: 修改节点时, 如果输入的是显示名称 (中文), 就出现错误信息

[jeeson]

例如刚才移动节点到 "问与答" 时, 代码错误, 后来才发现 需要输入 "qna"


另, 创建这个主题时, 也出现错误:

Traceback (most recent call last):
File "/base/python_runtime/python_lib/versions/1/google/appengine/ext/webapp/__init__.py", line 636, in __call__
handler.post(*groups)
File "/base/data/home/apps/v2ex/1.349548081764999296/topic.py", line 265, in post
topic.title = topic_title
File "/base/python_runtime/python_lib/versions/1/google/appengine/ext/db/__init__.py", line 593, in __set__
value = self.validate(value)
File "/base/python_runtime/python_lib/versions/1/google/appengine/ext/db/__init__.py", line 2596, in validate
raise BadValueError('Property %s is not multi-line' % self.name)
BadValueError: Property title is not multi-line