[Twisted-web] Nevow documentation style and other bugs

Hello! 1. I have attached the patch to issue 159 [1]. It fixes the style of the documentation in nevow-traversal.txt. Please take a look at it and report if the patch is acceptable. I can make similar patches to the rest of the documentation. 2. Then, I have found minor bug in nevow.url module. It is described in issue 165 [2]. Patch included. 3. There is still a bug in the Directory example in nevow-traversal.txt. Take a look at issue 158 [3]. I have made a patch, but I am not sure if it is okay. Thank you! [1] http://divmod.org/users/roundup.twistd/nevow/issue159 [2] http://divmod.org/users/roundup.twistd/nevow/issue165 [3] http://divmod.org/users/roundup.twistd/nevow/issue158 -- Best regards, Alexey.