Merge pull request #17 from matsu7874/master

Describe the current development style in README.

Author: matsu7874

README.md

@@ -1 +1,25 @@
 # ac-library-rs
+
+ac-library-rs is a rust port of AtCoder Library (ACL).
+
+See below for ACL.
+
+- [AtCoder Library (ACL) - AtCoder](https://atcoder.jp/posts/517)
+- [AtCoder Library - Codeforces](https://codeforces.com/blog/entry/82400)
+
+## Progress
+
+Our first milestone is 2020/09/20, when the first ACL contest is planned.
+We aim to implement the same toolset as original ACL(C++) on the day.
+
+We are trying to implement with the same files by referring to the original ACL's hpp.
+After that we try to improve our development flow, tests, or utilities.
+
+## How to contribute
+
+1. Create an issue or a draft PR before you start working.
+2. Make a PR and pass tests.
+
+## More information
+
+We have a slack workspace [rust-jp.rs](https://rust-jp.rs/). Please join it.