Use "" instead of <> to include files from simplefs
Implement file_operations.iterate instead of deprecated readdir

In newer version of kernel, since 3.11, readdir was dropped and the
replacment is iterate.
Merge pull request #1 from azat/readdir-to-iterate

Implement file_operations.iterate instead of deprecated readdir
Merge pull request #2 from azat/fix-includes

Use "" instead of <> to include files from simplefs
Update README