Rename `readdir` to `scandir`.
Add binding for `uv_thread_equal` and rename `UV::Thread.self` to `UV.thread_self`.
Fix define of `UV::FS.fd` to `UV::FS#fd`.
Support `uv_fs_access`.
Update version to v1.0.0-rc2.
Merge pull request #55 from take-cheeze/libuv-v1.0.0-rc2

Follow libuv v1.0.0 rc2 API.