Update CONTRIBUTING.md (#666)

* Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -1,28 +1,11 @@
 Contributing to IoTeX Core
 ============================
 
-The IoTeX Core project operates an open contributor model where anyone is welcome to contribute towards development in the form of peer review, testing and patches. This document explains the practical process and guidelines for contributing.
-
-Contributor Workflow
---------------------
-
-The codebase is maintained using the "contributor workflow" where everyone
-without exception contributes patch proposals using "pull requests". This
-facilitates social contribution, easy testing and peer review.
-
-To contribute a patch, the workflow is as follows:
-
-  1. Fork repository
-  1. Create topic branch
-  1. Commit patches
-
-In general commits should be atomic and diffs should be easy to read, and the [coding conventions](https://github.com/golang/go/wiki/CodeReviewComments)
-must be adhered to.
-
+The IoTeX Core project operates an open contributor model where anyone is welcome to contribute towards development in the form of peer review, testing and patches. If you are interested in contributing to the project then checkout the [Contributor's Guide](https://github.com/iotexproject/iotex-core/wiki/IoTex-Contributor-Guide)
 
 Copyright
 ---------
 
 By contributing to this repository, you agree to license your work under the 
 Apache 2.0 license. Any work contributed where you are not the original 
-author must contain its license header with the original author(s) and source.
+author must contain its license header with the original author(s) and source.