Improve title wrap on the tag page

[chengzhanhong]

I found a problem if a title is very long on the tag page. Suggest to change the flowing two lines to white-space: normal; https://github.com/chesterhow/tale/blob/de5cd20ac51a55607d7c4203f34b6b9e0696698f/_sass/tale/_tags.scss#L60

https://github.com/chesterhow/tale/blob/de5cd20ac51a55607d7c4203f34b6b9e0696698f/_sass/tale/_tags.scss#L75

The effect after the change can be found here