Following methods use corresponding File class methods
instead of IO class methods.

- Pathname#each_line
- Pathname#read
- Pathname#binread
- Pathname#write
- Pathname#binwrite
- Pathname#readlines

Reported by ooooooo_q.





git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66346 b2dd03c8-39d4-4d8f-98ff-823fe69b080e